Organogel

Abstract

This organogel comprises a polymer matrix and a plasticizer, wherein: the moisture content with respect to the total amount of the organogel is less than 1.0 mass%; a (meth)acrylic acid ester having an alicyclic hydrocarbon in the structure thereof is included as a polymerizable monomer constituting the polymer matrix; the plasticizer contains at least one selected from the group consisting of aliphatic hydrocarbons and fatty acid esters, and is liquid or paste at 25ºC; the initial adhesive strength to a bakelite plate is at least 1.0 N / 20 mm; and the adhesive strength retention rate after being immersed in water for one hour is at least 90%.

Description

Organogel

[0001] The present invention relates to organogels.

[0002] Gel-like materials have various properties such as water absorption, swelling, moisture retention, adhesiveness, conformability, cooling properties, and electrical conductivity. Taking advantage of these properties, they are used in a wide range of fields, including medicine, cosmetics, electricity, beauty and health equipment, sports, and food.

[0003] Gel materials can be broadly classified into hydrogels, in which the main solvent constituting the gel is water, and organogels, in which the main solvent constituting the gel is an organic solvent.

[0004] As an example of a hydrogel, Patent Document 1 discloses a hydrogel containing a polymer matrix, water, and a plasticizer, which is inhibited from swelling due to the infiltration of water from the outside and which maintains its initial high adhesive strength by reducing the loss of the plasticizer.

[0005] As an organogel, Patent Document 2 discloses a high-strength adhesive polymer gel formed from a polymer and a polyhydric alcohol. This adhesive gel has sufficient adhesive force and tensile strength.

[0006] Patent No. 7037639 Patent No. 5393147

[0007] When a gel material is applied directly to the skin, it is expected that the gel material will be directly exposed to water when bathing or washing the area around the application site with water, so it is desirable for the gel material to have excellent water resistance.

[0008] The hydrogel disclosed in Patent Document 1 has a problem in terms of water resistance, since it quickly falls off from the skin or device in water.

[0009] Conventional organogels are highly hydrophobic, and therefore have better water resistance than hydrogels, but lack sufficient adhesive strength. While the organogels disclosed in Prior Art Document 2 have improved adhesive strength, they still absorb moisture and swell when sweating during exercise or bathing, leaving problems in terms of water resistance and durability of adhesive strength.

[0010] The problem to be solved by the present invention is to provide an organogel that is excellent in water resistance, long-lasting adhesive strength, and appearance, and also has appropriate flexibility.

[0011] The present invention encompasses the following embodiments. [1] An organogel comprising a polymer matrix and a plasticizer, wherein the organogel has a water content of less than 1.0% by mass relative to the total amount of the organogel, wherein the polymer matrix comprises a (meth)acrylic acid ester having an alicyclic hydrocarbon in its structure as a polymerizable monomer, and wherein the plasticizer is a plasticizer that is liquid or paste-like at 25°C and comprises at least one member selected from the group consisting of an aliphatic hydrocarbon, a fatty acid ester, and a silicone oil, and wherein the organogel has an initial adhesive strength of 1.0 N / 20 mm or greater to a Bakelite plate and an adhesive strength retention rate of 90% or greater after immersion in water for 1 hour. [2] The organogel according to [1], wherein the (meth)acrylic acid ester having an alicyclic hydrocarbon in its structure comprises 4-t-butylcyclohexyl acrylate. [3] The organogel according to [1] or [2], wherein the polymerizable monomer constituting the polymer matrix further comprises at least one monomer selected from the group consisting of a (meth)acrylamide-based monomer and a (meth)acrylic acid ester-based monomer. [4] The organogel according to any one of [1] to [3], wherein the blending amount of the (meth)acrylic acid ester having an alicyclic hydrocarbon in its structure is 30 mass% or more relative to the total amount of the polymer matrix. [5] The organogel according to any one of [1] to [4], wherein the content of the plasticizer is 10 to 60 mass% relative to the total amount of the organogel. [6] The organogel according to any one of [1] to [5], wherein the thickness is in the range of 100 μm to 1000 μm.

[0012] According to the present invention, it is possible to provide an organogel that is excellent in water resistance, long-lasting adhesive strength, and appearance, and also has appropriate flexibility.

[0013] As used herein, the singular forms "a," "an," and "the" are intended to include both the singular and the plural unless otherwise expressly stated herein or clearly contradicted by context.

[0014] In this specification, the term "comprise" is a concept that encompasses "consist essentially only of" and "consist only of."

[0015] In the numerical ranges described in stages in this specification, the upper or lower limit of a certain numerical range can be arbitrarily combined with the upper or lower limit of another numerical range. Furthermore, in the numerical ranges described in this specification, the upper or lower limit of the numerical range may be replaced with a value shown in an example or a value that can be unambiguously derived from an example. Furthermore, in this specification, a numerical value connected with "to" means a numerical range that includes the numbers before and after "to" as the upper and lower limits.

[0016] According to one aspect of the present invention, there is provided an organogel comprising a polymer matrix and a plasticizer, wherein the organogel has a water content of less than 1.0 mass% relative to the total amount of the organogel, the polymer matrix comprises a (meth)acrylic acid ester having an alicyclic hydrocarbon in its structure as a polymerizable monomer, the plasticizer being liquid or paste-like at 25°C and comprising at least one member selected from the group consisting of aliphatic hydrocarbons, fatty acid esters, and silicone oils, and the organogel has an initial adhesive strength of 1.0 N / 20 mm or more to a Bakelite plate and an adhesive strength retention rate of 90% or more after immersion in water for 1 hour.

[0017] Polymer Matrix The polymer matrix is ​​not particularly limited as long as it can form an organogel.

[0018] The content of the polymer matrix in the organogel is not particularly limited, but is preferably in the range of 40 to 90 mass % relative to the total amount of the organogel, more preferably in the range of 50 to 80 mass %, and even more preferably in the range of 60 to 70 mass %.

[0019] The organogel of the present invention contains a (meth)acrylic acid ester having an alicyclic hydrocarbon in its structure as a polymerizable monomer constituting the polymer matrix. "In the structure" refers to within its own structure, i.e., within the structure of the (meth)acrylic acid ester. By including a (meth)acrylic acid ester having an alicyclic hydrocarbon in its structure as a polymerizable monomer constituting the polymer matrix, bleeding out of the plasticizer can be suppressed, resulting in an organogel with excellent appearance.

[0020] As the (meth)acrylic acid ester having an alicyclic hydrocarbon in its structure, for example, one or more selected from the group consisting of 4-t-butylcyclohexyl acrylate, isobornyl acrylate, 1,4-cyclohexanedimethanol monoacrylate, and 3,3,5-trimethylcyclohexyl acrylate can be used, and from the viewpoint of adhesive strength, it is preferable to use one or both of 4-t-butylcyclohexyl acrylate and 3,3,5-trimethylcyclohexyl acrylate.

[0021] From the viewpoint of obtaining an organogel that is excellent in water resistance, durability of adhesive strength, and appearance, the blending amount of the (meth)acrylic acid ester having an alicyclic hydrocarbon in its structure is preferably 30% by mass or more, more preferably 50% by mass or more, and even more preferably 70% by mass or more, based on the total amount of the polymer matrix.

[0022] Similarly, the content of structural units derived from a (meth)acrylic acid ester having an alicyclic hydrocarbon in the structure is preferably 30% by mass or more, more preferably 50% by mass or more, and even more preferably 70% by mass or more, relative to the total amount of the polymer matrix, from the viewpoint of obtaining an organogel that is excellent in water resistance, durability of adhesive strength, and appearance.

[0023] Furthermore, from the viewpoint of obtaining an organogel that is excellent in water resistance, durability of adhesive strength, and appearance, the blending amount of the (meth)acrylic acid ester having an alicyclic hydrocarbon in its structure is preferably within a range of 10 to 90 mass %, more preferably within a range of 40 to 80 mass %, and even more preferably within a range of 50 to 70 mass %, based on the total amount of the organogel.

[0024] Similarly, from the viewpoint of obtaining an organogel that is excellent in water resistance, durability of adhesive strength, and appearance, the content of structural units derived from a (meth)acrylic acid ester having an alicyclic hydrocarbon in the structure is preferably within a range of 10 to 90 mass %, more preferably within a range of 40 to 80 mass %, and even more preferably within a range of 50 to 70 mass %, relative to the total amount of the organogel.

[0025] In one embodiment of the present invention, the (meth)acrylic acid ester having an alicyclic hydrocarbon in its structure includes 4-t-butylcyclohexyl acrylate, which is preferred from the viewpoint of obtaining an organogel excellent in water resistance, durability of adhesive strength, and appearance.

[0026] In one embodiment of the present invention, the organogel further contains at least one monomer selected from the group consisting of (meth)acrylamide-based monomers and (meth)acrylic acid ester-based monomers as a polymerizable monomer constituting the polymer matrix, provided that neither the (meth)acrylamide-based monomers nor the (meth)acrylic acid ester-based monomers include (meth)acrylic acid esters having an alicyclic hydrocarbon in their structure.

[0027] The organogel contains, as the polymerizable monomer that constitutes the polymer matrix, at least one monomer selected from the group consisting of (meth)acrylamide-based monomers and (meth)acrylic acid ester-based monomers in addition to a (meth)acrylic acid ester having an alicyclic hydrocarbon in its structure, and this allows the physical properties of the organogel, such as adhesive strength and flexibility, to be adjusted.

[0028] Examples of (meth)acrylamide monomers include (meth)acrylamide; N,N-dialkyl(meth)acrylamides such as N,N-dimethyl(meth)acrylamide and N,N-diethyl(meth)acrylamide; N-alkyl(meth)acrylamides such as N-isopropyl(meth)acrylamide, N-methyl(meth)acrylamide, N-ethyl(meth)acrylamide and N-propyl(meth)acrylamide; N-ethoxymethyl(meth)acrylamide, N-propoxymethyl(meth)acrylamide, N-butoxymethyl(meth)acrylamide, N-isopropyl(meth)acrylamide, N-methyl(meth)acrylamide, N-ethyl(meth)acrylamide, N-propyl ... and derivatives thereof. Among these, one or more N-alkoxyalkyl(meth)acrylamides such as N,N-dimethyl(meth)acrylamide, N,N-diethyl(meth)acrylamide, N-isopropyl(meth)acrylamide, N-methyl(meth)acrylamide, N-ethyl(meth)acrylamide, and N-propyl(meth)acrylamide are preferred, although not limited thereto. In a particularly preferred embodiment, the (meth)acrylamide-based monomer comprises one or two monomers selected from the group consisting of N,N-dimethylacrylamide and N,N-diethylacrylamide.

[0029] Examples of (meth)acrylic acid ester monomers include, but are not limited to, one or more selected from the group consisting of (meth)acrylic acid alkyl esters in which the alkyl group has 1 to 18 carbon atoms, such as methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, n-hexyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-nonyl (meth)acrylate, isononyl (meth)acrylate, n-pentyl (meth)acrylate, n-decyl (meth)acrylate, isodecyl (meth)acrylate, n-lauryl (meth)acrylate, tridecyl (meth)acrylate, and n-stearyl (meth)acrylate. In a particularly preferred embodiment, the (meth)acrylic acid ester monomer comprises one or two monomers selected from the group consisting of n-octyl acrylate and isodecyl acrylate.

[0030] When the organogel contains at least one monomer selected from the group consisting of (meth)acrylamide-based monomers and (meth)acrylic acid ester-based monomers, the blending amount of the at least one monomer selected from the group consisting of (meth)acrylamide-based monomers and (meth)acrylic acid ester-based monomers is preferably within a range of 1.0 to 60% by mass, and more preferably within a range of 5.0 to 50% by mass, relative to the total amount of the polymer matrix, from the viewpoints of water resistance, durability of adhesive strength, and appearance.

[0031] Furthermore, the blending amount of at least one monomer selected from the group consisting of (meth)acrylamide-based monomers and (meth)acrylic acid ester-based monomers is preferably within a range of 1.0 to 40 mass %, more preferably within a range of 3.0 to 30 mass %, based on the total amount of the organogel, from the viewpoints of water resistance, durability of adhesive strength, and appearance.

[0032] A crosslinkable monomer may or may not be added as a monomer constituting the polymer matrix, but the addition of a crosslinkable monomer is preferred from the viewpoint of the shape retention of the organogel.

[0033] As the crosslinkable monomer, a monomer having two or more polymerizable carbon-carbon double bonds in the molecule can be preferably used.

[0034] Examples of crosslinkable monomers include methylene bis(meth)acrylamide, ethylene bis(meth)acrylamide, polyalkylene glycol dimethacrylates such as (poly)ethylene glycol di(meth)acrylate and (poly)propylene glycol di(meth)acrylate, polyfunctional (meth)acrylamides or polyfunctional (meth)acrylic acid esters such as glycerin di(meth)acrylate and glycerin tri(meth)acrylate, polyfunctional (meth)acrylic acid esters such as polyglycerin poly(meth)acrylate, tetraallyloxyethane, etc., which can be used alone or in combination of two or more. In a specific preferred embodiment, the crosslinkable monomer includes polyalkylene glycol dimethacrylate.

[0035] The amount of the crosslinkable monomer to be added is not particularly limited, but from the viewpoint of the adhesive strength and flexibility of the organogel, it is preferably in the range of 0.10 to 3.0 mass % relative to the total amount of the polymer matrix, and more preferably in the range of 0.50 to 2.0 mass %.

[0036] A polymerization initiator may be added to form the polymer matrix. The amount of the polymerization initiator is not particularly limited, but from the viewpoint of the strength and shape retention of the organogel, it is preferably in the range of 1.0 to 5.0 mass % relative to the total amount of the polymer matrix, and more preferably in the range of 1.0 to 3.0 mass %.

[0037] The type of polymerization initiator is not particularly limited, and may be a photopolymerization initiator or a thermal polymerization initiator. When the organogel is formed into a sheet, a photopolymerization initiator is preferably used. Examples of the photopolymerization initiator include acetophenone-based polymerization initiators, azo-based polymerization initiators, thioxanthone-based polymerization initiators, benzophenone-based polymerization initiators, acylphosphine oxide-based polymerization initiators, oxime ester-based polymerization initiators, benzoin-based polymerization initiators, and benzyl ketal-based polymerization initiators. More preferably, 2-hydroxy-2-methylpropiophenone can be used.

[0038] The polymer matrix may further contain components other than those described above, provided that the effects of the present invention are not impaired. The content and composition of the polymer matrix in the organogel can be appropriately adjusted so as to satisfy the above-mentioned numerical ranges for the initial adhesive strength, adhesive strength retention rate, and water content.

[0039] Plasticizer The plasticizer is a plasticizer that contains at least one selected from the group consisting of aliphatic hydrocarbons, fatty acid esters, and silicone oils and is liquid or pasty at 25° C. By adding a plasticizer of this composition, an organogel with excellent water resistance and appropriate elasticity can be obtained.

[0040] Examples of aliphatic hydrocarbons include liquid paraffin, squalane, hydrogenated polyisobutene, hydrogenated polydecene, etc. From the viewpoint of obtaining excellent water resistance and appropriate elasticity, it is preferable that the aliphatic hydrocarbon contains one or more selected from the group consisting of liquid paraffin, squalane, hydrogenated polyisobutene, and hydrogenated polydecene.

[0041] Examples of fatty acid esters include glycerin fatty acid esters, polyglycerin fatty acid esters, propylene glycol fatty acid esters, sorbitan fatty acid esters, and fatty acid methyl esters, and more specifically, castor oil and glyceryl triisostearate are mentioned. From the viewpoint of obtaining excellent water resistance and appropriate elasticity, it is preferable that the fatty acid ester contains one or more selected from the group consisting of glycerin fatty acid esters, polyglycerin fatty acid esters, propylene glycol fatty acid esters, sorbitan fatty acid esters, and fatty acid methyl esters. More specifically, it is preferable that the fatty acid ester contains one or both of castor oil and glyceryl triisostearate.

[0042] Examples of silicone oils include straight silicone oil, cyclic silicone oil, methyl hydrogen silicone oil, branched silicone oil, alkyl-modified silicone oil, alcohol-modified silicone oil, amino-modified silicone oil, etc. From the viewpoint of obtaining excellent water resistance and appropriate elasticity, it is preferable that the silicone oil contains one or more selected from the group consisting of straight silicone oil, cyclic silicone oil, methyl hydrogen silicone oil, branched silicone oil, alkyl-modified silicone oil, alcohol-modified silicone oil, and amino-modified silicone oil.

[0043] The content of the plasticizer is not particularly limited, but is preferably in the range of 15 to 120 mass % relative to the total amount of the polymer matrix, more preferably in the range of 20 to 120 mass %, even more preferably in the range of 40 to 100 mass %, and particularly preferably in the range of 50 to 80 mass %.

[0044] The content of the plasticizer is not particularly limited, but is preferably in the range of 10 to 60 mass % relative to the total amount of the organogel, more preferably in the range of 25 to 55 mass %, and even more preferably in the range of 35 to 50 mass %.

[0045] The content and composition of the plasticizer in the organogel can be appropriately adjusted so as to satisfy the above-mentioned numerical ranges for the initial adhesive strength, adhesive strength retention rate, and water content.

[0046] The organogel of the present invention has a water content of less than 1.0% by mass. From the viewpoint of hydrolysis, the water content of the organogel is preferably less than 0.80% by mass, more preferably less than 0.50% by mass, relative to the total amount of the organogel, and particularly preferably zero.

[0047] Water Content of Organogel The water content of the organogel can be measured by the following method.

[0048] A given mass of organogel is weighed out, placed in a vial, and sealed with an aluminum cap to form a test sample. The test sample is placed in a moisture vaporizer. The vial is then heated to 125°C to vaporize the water in the sample, and the mass of the vaporized water is measured using a moisture measuring device. The measured mass of vaporized water is divided by the mass of the weighed organogel, and this value is multiplied by 100 to determine the moisture content (%) of the organogel. The moisture content of the organogel can typically be measured by the method described in the Examples.

[0049] The organogel of the present invention may contain other components as needed, such as rust inhibitors, antifungals, antioxidants, antifoaming agents, stabilizers, surfactants, colorants, thickeners, moisturizers, and fragrances.

[0050] Examples of thickeners include, but are not limited to, dextrin fatty acid esters, polyethylene wax, inorganic fillers, silica particles, cellulose fibers, etc. In certain preferred embodiments, the thickener comprises one or more selected from the group consisting of dextrin fatty acid esters, silica particles, and cellulose fibers.

[0051] Examples of moisturizing agents include, but are not limited to, skin and nail care oils and skin conditioning agents such as shea butter, jojoba oil, apricot kernel oil, almond oil, olive fruit oil, etc. In certain preferred embodiments, the moisturizing agent comprises one or more selected from the group consisting of shea butter, jojoba oil, and almond oil.

[0052] Examples of flavoring agents include, but are not limited to, menthol, fragrance oils, etc. In certain preferred embodiments, the flavoring agent comprises one or more selected from the group consisting of menthol and fragrance oils.

[0053] The organogel of the present invention has an initial adhesive strength of 1.0 N / 20 mm or more to a Bakelite plate and an adhesive strength retention rate of 90% or more after immersion in water for 1 hour, thereby exhibiting excellent adhesive strength durability, water resistance, and adhesive properties.

[0054] Initial Adhesion Strength to Bakelite Plate The initial adhesion strength of the organogel to a Bakelite plate can be measured by the following method.

[0055] A test specimen is an organogel formed into a sheet and covered on both sides with a PET film. The PET film on one side of the test specimen is peeled off, and the peeled side is attached to a Bakelite plate. The Bakelite plate is then set in a tensile tester, and the load applied when peeling the test specimen in a 90° direction at a rate of 300 mm / min in accordance with JIS Z 0237 under an environment of 23°C and 55% relative humidity is measured. The measured load (N / 20 mm) is taken as the initial adhesive strength (F0) to the Bakelite plate. A Tensilon "RTE-1210" (manufactured by Orientec Co., Ltd.) can be preferably used as the tensile tester. The initial adhesive strength to the Bakelite plate can typically be measured by the method described in the Examples.

[0056] From the viewpoint of adhesive strength and durability, the initial adhesive strength to a Bakelite plate is preferably 1.0 N / 20 mm or more, more preferably 5 N / 20 mm or more, and even more preferably 10 N / 20 mm or more.

[0057] Adhesion Retention Rate of Organogel The adhesion retention rate of an organogel can be measured by the following method.

[0058] The organogel was formed into a sheet and covered on both sides with PET film. The PET film on one side of the test piece was peeled off, and the test piece was immersed in water for 1 hour. The test piece was then removed from the water and the surface moisture was removed. The peeled side of the test piece was attached to a Bakelite plate, and the Bakelite plate was placed in a tensile tester. According to JIS Z 0237, the load required to peel the test piece in a 90° direction at a rate of 300 mm / min under an environment of 23°C and 55% relative humidity was measured. The measured load (N / 20 mm) was taken as the adhesive strength (F1) of the organogel after immersion in water. The adhesive strength retention (%) of the organogel was calculated by dividing the adhesive strength (F1) of the organogel after immersion in water by the initial adhesive strength (F0) to the Bakelite plate and multiplying this value by 100 [adhesive strength retention (%) = F1 / F0 × 100]. The adhesive strength retention rate of the organogel can typically be measured by the method described in the Examples.

[0059] From the viewpoint of water resistance, the adhesive strength retention rate of the organogel is preferably 90% or more, more preferably 93% or more, and even more preferably 95% or more.

[0060] The shape of the organogel of the present invention is not particularly limited, and may be a sheet or any three-dimensional shape, preferably a sheet. The shape of the organogel sheet may be any shape depending on the purpose, including, but not limited to, a substantially rectangular or substantially circular shape.

[0061] The thickness of the organogel can be adjusted according to the application and is not particularly limited, but from the viewpoint of adhesive strength, it is preferably in the range of 100 μm to 1000 μm, and more preferably in the range of 300 μm to 600 μm.

[0062] Method for Producing Organogel The organogel of the present invention can be produced by the following method.

[0063] The method includes first mixing a (meth)acrylic acid ester having an alicyclic hydrocarbon with a plasticizer to obtain a mixed solution. The mixed solution may further contain at least one monomer selected from the group consisting of (meth)acrylamide-based monomers and (meth)acrylic acid ester-based monomers, a crosslinkable monomer, a polymerization initiator, and one or more additives (rust inhibitors, antifungal agents, antioxidants, antifoaming agents, stabilizers, surfactants, colorants and thickeners, moisturizers, and fragrances). The inclusion of a polymerization initiator in the mixed solution promotes polymerization of the (meth)acrylic acid ester. These materials are as described above as components of the organogel.

[0064] When mixing the (meth)acrylic acid ester having an alicyclic hydrocarbon and the plasticizer, these components may be mixed at once or may be mixed separately.

[0065] Next, the mixed solution is poured into a container or the like having a desired shape and cured to form an organogel. When forming into a sheet, for example, the mixed solution is dropped onto a film, which is then covered with a PET film, the mixed solution is uniformly spread, fixed to a desired thickness, and cured to form an organogel.

[0066] The curing method is not particularly limited, and any known method can be used. When curing is performed by a polymerization reaction caused by ultraviolet irradiation, the cumulative irradiation amount of ultraviolet rays is 1000 mJ / cm ２ It is desirable that this is the case.

[0067] Typically, the organogel is prepared as described in the Examples.

[0068] According to this method, it is possible to produce an organogel comprising a polymer matrix and a plasticizer, wherein the organogel has a water content of less than 1 mass% relative to the total amount of the organogel, the polymer matrix contains a (meth)acrylic acid ester having an alicyclic hydrocarbon in its structure as a polymerizable monomer, the plasticizer is a plasticizer that is liquid or paste-like at 25°C and contains one member selected from the group consisting of aliphatic hydrocarbons and fatty acid esters, and the organogel has an initial adhesive strength of 1.0 N / 20 mm or more to a Bakelite plate and an adhesive strength retention rate of 90% or more after immersion in water for 1 hour.

[0069] Further Structure of Organogel The organogel can be configured such that its surface in contact with the outside world is covered with a substrate made of woven fabric, nonwoven fabric, film, or the like. Only one surface may be covered, or multiple surfaces may be covered. An intermediate substrate made of woven fabric, nonwoven fabric, or the like may also be embedded in the organogel. The substrate or intermediate substrate reinforces the organogel and improves its shape retention when cut.

[0070] The nonwoven fabric and woven fabric may be made of natural fibers such as cellulose, silk, or hemp, or synthetic fibers such as polyester, nylon, rayon, polyethylene, polypropylene, or polyurethane, or a blend thereof, and a binder may be used as needed.The film may be made of polyester, nylon, polyethylene, polypropylene, or polyurethane.

[0071] The manufacturing method of the nonwoven fabric is not particularly limited, but examples thereof include dry method, wet method, spunbond method, meltblown method, airlaid method, chemical bond method, thermal bond method, needle punch method, and hydroentanglement method. It is more preferable to adopt a manufacturing method according to the basis weight and material, and to avoid unevenness in the basis weight for position control of the intermediate substrate. The woven fabric is also not particularly limited, and can be selected appropriately, such as plain weave, tricot, or Russell.

[0072] The basis weight of the woven or nonwoven fabric is not particularly limited, but is, for example, 10 to 40 g / m ２ It is preferable that the density is 10 to 28 g / m ２The thickness of the intermediate substrate is not particularly limited, and is preferably 50 to 1000 μm, more preferably 50 to 500 μm, and even more preferably 80 to 300 μm.

[0073] The organogel of the present invention can also be used in combination with known materials. Because the organogel of the present invention has moderate elasticity, excellent water resistance, and excellent adhesive strength and appearance, it can be used in a wide range of fields, including medicine, cosmetics, food, chemistry, bioengineering, and sports. For example, it can be suitably used as an organogel that is attached to a living body, such as in monitoring devices for electrocardiograms and the like, medical electrodes in devices that perform treatment using low-, medium-, or high-frequency electrical stimulation, skin patches in devices that perform examinations using ultrasound, return electrodes for electric scalpels, and adhesives for nail tips.

[0074] The present invention will be described in more detail using examples, but the present invention is not limited to these examples.

[0075] 1. Production of Organogel (Example 1) First, 2.0 parts by mass of 2-hydroxy-2-methylpropiophenone (trade name "Omnirad 1173", manufactured by IGM Resins B.V.) as a polymerization initiator was added to 100 parts by mass of 4-t-butylcyclohexyl acrylate (trade name "TBCHA", manufactured by KJ Chemicals Co., Ltd.), and the mixture was stirred to completely dissolve. To the resulting solution, 66.6 parts by mass of liquid paraffin (trade name "Liquid Paraffin No. 380-S", manufactured by Sanko Chemical Industry Co., Ltd.) as a plasticizer was added and stirred to obtain a colorless, transparent monomer blend liquid. Next, the resulting monomer blend liquid was dropped onto a silicone-coated PET film. A similar silicone-coated PET film was placed on top of the film to uniformly spread the liquid and fix it to a thickness of 300 μm. A metal halide lamp was used to illuminate the film with an energy dose of 3000 mJ / cm. ２ By irradiating the organogel with ultraviolet rays of 300 .mu.m in thickness, a sheet-like organogel was produced.

[0076] Example 2 An organogel was produced in the same manner as in Example 1, except that, when obtaining a monomer mixture, 2.0 parts by mass of 2-hydroxy-2-methylpropiophenone as a polymerization initiator was added to 100 parts by mass of 3,3,5-trimethylcyclohexyl acrylate (trade name "TMCHA", manufactured by Osaka Organic Chemical Industry Ltd.), the mixture was stirred to completely dissolve, and 66.6 parts by mass of liquid paraffin No. 380-S as a plasticizer was added to the obtained solution, followed by stirring to obtain a colorless and transparent monomer mixture.

[0077] Example 3 An organogel was produced in the same manner as in Example 1, except that 1.0 part by mass of polyalkylene glycol dimethacrylate (trade name "BLEMMER PDE-400", manufactured by NOF Corporation) was added as a crosslinkable monomer to 100 parts by mass of 4-t-butylcyclohexyl acrylate when preparing the monomer mixture liquid.

[0078] Example 4 An organogel was produced in the same manner as in Example 1, except that 42.9 parts by mass of liquid paraffin No. 380-S was added as a plasticizer when the monomer mixture liquid was obtained.

[0079] Example 5 An organogel was produced in the same manner as in Example 1, except that 100 parts by mass of liquid paraffin No. 380-S was added as a plasticizer when the monomer mixture liquid was obtained.

[0080] Example 6 An organogel was produced in the same manner as in Example 1, except that, when obtaining the monomer mixture liquid, 2 parts by mass of 2-hydroxy-2-methylpropiophenone as a polymerization initiator was added to 100 parts by mass of a mixed liquid of 50 parts by mass of 4-t-butylcyclohexyl acrylate and 50 parts by mass of n-octyl acrylate (trade name "NOAA", manufactured by Osaka Organic Chemical Industry Ltd.), and the mixture was stirred and completely dissolved.

[0081] Example 7 An organogel was produced in the same manner as in Example 1, except that, when obtaining the monomer mixture liquid, 2.0 parts by mass of 2-hydroxy-2-methylpropiophenone was added as a polymerization initiator to 100 parts by mass of a mixed liquid of 75 parts by mass of 4-t-butylcyclohexyl acrylate and 25 parts by mass of isodecyl acrylate (trade name "IDAA", manufactured by Osaka Organic Chemical Industry Ltd.), and the mixture was stirred and completely dissolved.

[0082] Example 8 An organogel was produced in the same manner as in Example 1, except that, when obtaining the monomer mixture liquid, 2.0 parts by mass of 2-hydroxy-2-methylpropiophenone was added as a polymerization initiator to 100 parts by mass of a mixed liquid of 95 parts by mass of 4-t-butylcyclohexyl acrylate and 5 parts by mass of N,N-diethylacrylamide (trade name "DEAA", manufactured by KJ Chemicals Co., Ltd.), and the mixture was stirred and completely dissolved.

[0083] Example 9 An organogel was produced in the same manner as in Example 1, except that, when obtaining the monomer mixture, 2.0 parts by mass of 2-hydroxy-2-methylpropiophenone was added as a polymerization initiator to 100 parts by mass of a mixture of 95 parts by mass of 4-t-butylcyclohexyl acrylate and 5 parts by mass of N,N-dimethylacrylamide (trade name "DMAA", manufactured by KJ Chemicals Co., Ltd.), and the mixture was stirred and completely dissolved.

[0084] (Example 10) An organogel was produced in the same manner as in Example 1, except that 66.6 parts by mass of isohexadecane (trade name "Permethyl 101A", manufactured by Nihon Koken Kogyo Co., Ltd.) was added as a plasticizer and 2.0 parts by mass of polyalkylene glycol dimethacrylate was added as a cross-linkable monomer when obtaining the monomer mixture liquid.

[0085] (Example 11) An organogel was produced in the same manner as in Example 1, except that 66.6 parts by mass of squalane (trade name "Olive Squalane", manufactured by Kokyu Alcohol Kogyo Co., Ltd.) was added as a plasticizer and 2.0 parts by mass of polyalkylene glycol dimethacrylate was added as a cross-linkable monomer when obtaining the monomer mixture liquid.

[0086] Example 12 An organogel was produced in the same manner as in Example 1, except that, when obtaining the monomer mixture liquid, 66.6 parts by mass of hydrogenated polyisobutene (trade name "Pearleam 6", manufactured by NOF Corporation) was added as a plasticizer, and 2 parts by mass of polyalkylene glycol dimethacrylate was added as a cross-linkable monomer.

[0087] Example 13 An organogel was produced in the same manner as in Example 1, except that 66.6 parts by mass of hydrogenated polydecene (trade name "SILKFLO 366", manufactured by INEOS Oligomers USA LLC) was added as a plasticizer and 2 parts by mass of polyalkylene glycol dimethacrylate was added as a cross-linkable monomer when obtaining the monomer mixture liquid.

[0088] (Example 14) An organogel was produced in the same manner as in Example 1, except that 66.6 parts by mass of castor oil (trade name "Marutoku A", manufactured by Ito Oil Mills, Ltd.) was added as a plasticizer and 2.0 parts by mass of polyalkylene glycol dimethacrylate was added as a cross-linkable monomer when obtaining the monomer mixture liquid.

[0089] Example 15 An organogel was produced in the same manner as in Example 1, except that 66.6 parts by mass of glyceryl triisostearate (trade name "Sun Oil O-183", manufactured by Taiyo Kagaku Co., Ltd.) was added as a plasticizer when the monomer mixture liquid was obtained.

[0090] Example 16 An organogel was produced in the same manner as in Example 1, except that 50 parts by mass of liquid paraffin No. 380-S and 16.6 parts by mass of silicone oil (trade name "KF-96A-6CS", manufactured by Shin-Etsu Chemical Co., Ltd.) were added as plasticizers when the monomer mixture was obtained.

[0091] Example 17 An organogel was produced in the same manner as in Example 1, except that, when obtaining the monomer mixture liquid, 58.3 parts by mass of liquid paraffin No. 380-S was added as a plasticizer, 8.3 parts by mass of shea butter (product name "Shea Butter RF", manufactured by Kokyu Alcohol Kogyo Co., Ltd.) was added as a moisturizer, and 1.0 part by mass of polyalkylene glycol dimethacrylate was added as a crosslinkable monomer.

[0092] Comparative Example 1 An organogel was produced in the same manner as in Example 1, except that 66.6 parts by mass of polyoxypropylene diglyceryl ether (trade name "SC-P1000", manufactured by Sakamoto Yakuhin Kogyo Co., Ltd.) was added as a plasticizer when obtaining the monomer mixture liquid.

[0093] Comparative Example 2 An organogel was produced in the same manner as in Example 1, except that 66.6 parts by mass of polyoxyethylene methyl glucoside (product name "MG-10E", manufactured by NOF Corporation) was added as a plasticizer when the monomer mixture liquid was obtained.

[0094] Comparative Example 3 An organogel was produced in the same manner as in Example 1, except that, when obtaining a monomer mixture liquid, 2 parts by mass of 2-hydroxy-2-methylpropiophenone as a polymerization initiator was added to 100 parts by mass of 1,4-cyclohexanedimethanol monoacrylate (trade name "CHDMMA", manufactured by Nippon Kasei Chemical Co., Ltd.), the mixture was stirred to completely dissolve, and 66.6 parts by mass of SC-P1000 as a plasticizer was added to the obtained solution, followed by stirring to obtain a colorless and transparent monomer mixture liquid.

[0095] Comparative Example 4 An organogel was produced in the same manner as in Example 1, except that 66.6 parts by mass of castor oil (product name "Castor Hardened Oil A", manufactured by Ito Oil Mills, Ltd.), which is solid at 25°C, was added as a plasticizer when the monomer mixture liquid was obtained.

[0096] Comparative Example 5 An organogel was produced in the same manner as in Example 1, except that 66.6 parts by mass of an alkyl silicone (trade name "Microcare Silicone W3045", manufactured by Thor Japan Co., Ltd.) that is solid at 25°C was added as a plasticizer when the monomer mixture liquid was obtained.

[0097] Comparative Example 6 An organogel was produced in the same manner as in Example 1, except that, when obtaining a monomer mixture, 2.0 parts by mass of 2-hydroxy-2-methylpropiophenone was added as a polymerization initiator to 100 parts by mass of n-octyl acrylate, 2 parts by mass of Blemmer PDE-400 was added as a crosslinkable monomer, the mixture was stirred to achieve complete dissolution, and 66.6 parts by mass of liquid paraffin No. 380-S was added as a plasticizer to the obtained solution, followed by stirring to obtain a colorless and transparent monomer mixture.

[0098] Comparative Example 7 An organogel was produced in the same manner as in Example 1, except that, when obtaining a monomer mixture, 2.0 parts by mass of 2-hydroxy-2-methylpropiophenone was added as a polymerization initiator, 2 parts by mass of polyalkylene glycol dimethacrylate was added as a crosslinkable monomer, and the mixture was stirred to completely dissolve. To the resulting solution, 66.6 parts by mass of liquid paraffin No. 380-S was added as a plasticizer, and the mixture was stirred to obtain a colorless, transparent monomer mixture.

[0099] Comparative Example 8 An organogel was produced in the same manner as in Example 1, except that, when obtaining a monomer mixture, 2 parts by mass of 2-hydroxy-2-methylpropiophenone as a polymerization initiator and 2.0 parts by mass of polyalkylene glycol dimethacrylate as a crosslinkable monomer were added to 100 parts by mass of 2-ethylhexyl acrylate (trade name "2-EHA", manufactured by Mitsubishi Chemical Corporation), the mixture was stirred to achieve complete dissolution, and 66.6 parts by mass of liquid paraffin No. 380-S as a plasticizer was added to the obtained solution and the mixture was stirred to obtain a colorless, transparent monomer mixture.

[0100] Comparative Example 9 An organogel was produced in the same manner as in Example 1, except that, when obtaining a monomer mixture, 2.0 parts by mass of 2-hydroxy-2-methylpropiophenone as a polymerization initiator and 2 parts by mass of polyalkylene glycol dimethacrylate as a crosslinkable monomer were added to 100 parts by mass of butyl acrylate (trade name "BA", manufactured by Mitsubishi Chemical Corporation), the mixture was stirred to achieve complete dissolution, and 66.6 parts by mass of liquid paraffin No. 380-S as a plasticizer was added to the obtained solution and the mixture was stirred to obtain a colorless and transparent monomer mixture.

[0101] Comparative Example 10 An organogel was produced in the same manner as in Example 1, except that, when obtaining a monomer mixture, 2 parts by mass of 2-hydroxy-2-methylpropiophenone as a polymerization initiator and 2.0 parts by mass of polyalkylene glycol dimethacrylate as a crosslinkable monomer were added to 100 parts by mass of lauryl acrylate (trade name "LA", manufactured by Osaka Organic Chemical Industry Ltd.), the mixture was stirred to achieve complete dissolution, and 66.6 parts by mass of liquid paraffin No. 380-S as a plasticizer was added to the obtained solution and the mixture was stirred to obtain a colorless, transparent monomer mixture.

[0102] 2. Measurement or Evaluation Methods and Evaluation Criteria (1) Evaluation of Gel Formability The compositions obtained in Examples 1 to 17 and Comparative Examples 1 to 10 were visually observed for gel formability and evaluated based on the following criteria: Pass: Solid with overall shape retention, no cracks or breakage observed when bent 180°. Fail: Liquid or paste-like without overall shape retention, even if solid with overall shape retention, cracks or breakage observed when bent 180°. The organogels of Examples 1 to 17 and Comparative Examples 3, 6 to 8, and 10 that passed the evaluation of gel formability were further subjected to the tests and evaluations (2) to (7) below.

[0103] (2) Evaluation of Gel Appearance The appearance of each organogel obtained in Examples 1 to 17 and Comparative Examples 3, 6 to 8, and 10 was visually observed and evaluated based on the following criteria: Good: The gel is transparent. Poor: The gel is cloudy or there is bleeding of the plasticizer.

[0104] (3) Measurement of Water Content of Gels 100 mg of each organogel obtained in Examples 1 to 17 and Comparative Examples 3, 6 to 8, and 10 was weighed out, placed in a vial, and sealed with an aluminum cap to prepare a test sample. The test sample was placed in a moisture vaporizer ("VA-230" manufactured by Mitsubishi Chemical Analytech Co., Ltd.). The vial was then heated to 125°C to vaporize the water in the sample, and the vaporized water was measured using a moisture measuring device ("KF-200" manufactured by Mitsubishi Chemical Analytech Co., Ltd.). The measured value (mg) was divided by the mass (100 mg) of the weighed organogel, and the resulting value was multiplied by 100 to obtain the water content (%) of the organogel.

[0105] (4) Measurement of Initial Adhesion Strength The organogels obtained in Examples 1 to 17 and Comparative Examples 3, 6 to 8, and 10 were each cut into a size of 20 mm wide x 120 mm long to prepare test specimens. The PET film on one side of the test specimen was peeled off, and the peeled surface was attached to a Bakelite plate and set in a Tensilon ("RTE-1210" manufactured by Orientec Co., Ltd.). The load required to peel the test specimen in a 90° direction at a rate of 300 mm / min was measured in accordance with JIS Z 0237 under an environment of 23°C and 55% relative humidity, and the measured load value (N / 20 mm) was taken as the initial adhesive strength of the organogels.

[0106] (5) Measurement of Adhesion Strength After Immersion in Water The organogels obtained in Examples 1 to 17 and Comparative Examples 3, 6 to 8, and 10 were each cut into a size of 20 mm wide x 120 mm long to prepare test specimens. The PET film on one side of each test specimen was peeled off, and the specimen was immersed in water for 1 hour and allowed to stand. The specimen was then removed from the water and the surface moisture was removed. The peeled side of the specimen was then attached to a Bakelite plate, and the load applied when peeling the specimen in a 90° direction at a rate of 300 mm / min in accordance with JIS Z 0237 under an environment of 23°C and 55% relative humidity was measured. The measured load value (N / 20 mm) was taken as the adhesive strength of the organogels after immersion in water.

[0107] (6) Calculation of Adhesion Retention Rate The adhesion retention rate was calculated using the following formula: Adhesion retention rate (%) = F1 / F0 x 100 F0: initial adhesion rate of the organogel F1: adhesion rate of the organogel after immersion in water

[0108] (7) Evaluation of Long-Term Adhesion Each organogel obtained in Examples 1 to 17 and Comparative Examples 3, 6 to 8, and 10 was cut into a circle with a diameter of 3 cm, the PET film on one side was peeled off, and a nonwoven fabric (trade name "Sontara", Nissei Corporation) was attached as a surface material to obtain a patch sample. The PET film on the other side of the patch sample was peeled off and the patch sample was attached to human skin (chest) to evaluate long-term adhesion. A: Can be worn continuously for one week or more B: Can be worn for one day or more, but the patch sample falls off from the skin in less than one week C: The patch sample falls off from the skin in less than one day (less than 24 hours). The results of the evaluations and measurements in (1) to (7) above are shown in Tables 1 and 2.

[0109]

[0110]

Claims

1. An organogel comprising a polymer matrix and a plasticizer, wherein the organogel has a water content of less than 1.0% by mass relative to the total amount of the organogel, wherein the polymer matrix contains a (meth)acrylic acid ester having an alicyclic hydrocarbon in its structure as a polymerizable monomer, and wherein the plasticizer is a liquid or paste-like plasticizer at 25°C that contains at least one member selected from the group consisting of aliphatic hydrocarbons, fatty acid esters, and silicone oils, and wherein the organogel has an initial adhesive strength of 1.0 N / 20 mm or more to a Bakelite plate and an adhesive strength retention rate of 90% or more after immersion in water for 1 hour.

2. The organogel according to claim 1, wherein the (meth)acrylic acid ester having an alicyclic hydrocarbon in its structure includes 4-t-butylcyclohexyl acrylate.

3. The organogel described in claim 1, further comprising at least one monomer selected from the group consisting of (meth)acrylamide-based monomers and (meth)acrylic acid ester-based monomers as the polymerizable monomer constituting the polymer matrix.

4. The organogel according to claim 1, wherein the amount of the (meth)acrylic acid ester having an alicyclic hydrocarbon in its structure is 30% by mass or more relative to the total amount of the polymer matrix.

5. The organogel according to claim 1, wherein the content of the plasticizer is 10 to 60% by mass based on the total amount of the organogel.

6. The organogel according to any one of claims 1 to 5, having a thickness in the range of 100 μm to 1000 μm.