(METH)acrylic resin composition

Abstract

To provide a (meth)acrylic resin composition having antiviral property and antistatic property.SOLUTION: A (meth)acrylic resin composition is provided, containing soft material having at least one of a (meth)acrylic resin and a glass transition temperature (Tg) of -30°C or lower, and glyceryl fatty acid ester, and when the total of contents of the soft material having at least one of the (meth)acrylic resin and the glass transition temperature (Tg) of -30°C or lower, and the glyceryl fatty acid ester in the (meth)acrylic resin composition is 100 mass%, a content of the (meth)acrylic resin is within a range of 35 mass% or more and 84 mass% or less, a content of the soft material having at least one of the glass transition temperature (Tg) of -30°C or lower is within a range of 15 mass% or more and 60 mass% or less, and a content of the glyceryl fatty acid ester is within a range of 1 mass% or more and 15 mass% or less.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a (meth)acrylic resin composition, a sheet formed from the (meth)acrylic resin composition, and further to a laminate including the sheet. [Background technology]

[0002] A thermoplastic polymer composition containing an acrylic block copolymer and an acrylic resin, which is intended to provide a sheet-like molded product having excellent surface smoothness, excellent moldability, and excellent flexibility and high light transmittance for short wavelength light, and a thermoplastic polymer composition for forming a sheet-like molded product, is known (see Patent Document 1).

[0003] Also, an embodiment is known in which a glycerin monofatty acid ester is blended with a (meth)acrylic resin composition for the purpose of improving the antistatic properties of the (meth)acrylic resin composition (see Patent Document 2). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2010 / 055798 [Patent Document 2] Japanese Patent Application Publication No. 5-239305 Summary of the Invention [Problem to be solved by the invention]

[0005] Due to the recent spread of the COVID-19 pandemic, it is desired to impart antiviral properties to devices, instruments, etc. that may come into contact with the human body, and the same is true for devices, instruments, etc. that contain, for example, components, molded articles obtained by molding (meth)acrylic resin compositions in a manner that they come into contact with the human body.

[0006] However, in the (meth)acrylic resin compositions and molded articles thereof described in Patent Documents 1 and 2, no consideration is given to imparting antiviral properties against, for example, the novel coronavirus. Even if the compositions were able to exhibit antiviral properties, for example, from the viewpoint of preventing infection with the novel coronavirus, surface treatment with ethanol (alcohol disinfection treatment) is recommended for treating equipment, tools, etc., and may result in the equipment, tools, etc. losing their antiviral properties or even their antistatic properties. [Means for solving the problem]

[0007] The present inventors have conducted intensive research to solve the above-mentioned problems, and have found that the above-mentioned problems can be solved by using a (meth)acrylic resin composition containing a (meth)acrylic resin, a soft material having at least one glass transition temperature (Tg) of -30°C or lower, and a predetermined amount of a glycerin fatty acid ester, thereby completing the present invention.

[0008] That is, the present invention provides the following [1] to

[11] . [1] A (meth)acrylic resin composition comprising a (meth)acrylic resin, at least one soft material having a glass transition temperature (Tg) of -30°C or lower, and a glycerin fatty acid ester, In the (meth)acrylic resin composition, when the total content of the (meth)acrylic resin, the soft material having at least one glass transition temperature (Tg) of -30°C or lower, and the glycerin fatty acid ester is taken as 100 mass%, the content of the (meth)acrylic resin is in the range of 35 mass% or more and 84 mass% or less, The content of at least one soft material having a glass transition temperature (Tg) of -30°C or lower is in the range of 15% by mass or more and 60% by mass or less, A (meth)acrylic resin composition having a glycerin fatty acid ester content of 1% by mass or more and 15% by mass or less. [2] The (meth)acrylic resin composition according to [1], wherein the soft material having at least one glass transition temperature (Tg) of −30° C. or lower is an acrylic soft material. [3] The (meth)acrylic resin composition according to [2], wherein the acrylic soft material is an acrylic block copolymer. [4] The acrylic block copolymer is a methacrylate polymer block; Acrylate polymer block and The (meth)acrylic resin composition according to [3], which is a block copolymer comprising: [5] The acrylic block copolymer is The content of the methacrylic acid ester polymer block is in the range of 30% by mass or more and 60% by mass or less, The (meth)acrylic resin composition according to [4], which is a block copolymer having an acrylic acid ester polymer block content in the range of 40% by mass or more and 70% by mass or less. [6] The (meth)acrylic resin composition according to any one of [1] to [5], wherein the glycerin fatty acid ester has an HLB value in the range of 5 or more and 12 or less. [7] The (meth)acrylic resin composition according to [6], wherein the glycerin fatty acid ester is a glycerin saturated fatty acid ester. [8] A preform obtained by molding the (meth)acrylic resin composition according to any one of [1] to [7]. [9] The base material according to [8], which is a sheet formed from the (meth)acrylic resin composition.

[10] A laminated sheet comprising one or more layers of the sheet according to [9].

[11] The laminate sheet according to

[10] , further comprising a base layer, and layers of the (meth)acrylic resin composition are provided on both a first main surface and a second main surface facing each other in a thickness direction of the base layer so as to sandwich the base layer. Effect of the Invention

[0009] According to the present invention, it is possible to provide a (meth)acrylic resin composition that can maintain antiviral properties against, for example, the novel coronavirus even after multiple surface treatments with ethanol in a raw material (molded body) obtained by molding the (meth)acrylic resin composition, and can further suppress the generation of static electricity and the adhesion of dust due to the generation of static electricity. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, the embodiments of the present invention will be described in detail. Note that the present invention is not limited to the following description. The embodiments described below can be appropriately modified without departing from the gist of the present invention.

[0011] The (meth)acrylic resin composition according to the present embodiment is a (meth)acrylic resin composition containing a (meth)acrylic resin, a soft material having at least one glass transition temperature (Tg) of -30°C or lower, and a glycerin fatty acid ester, in which, when the total content of the (meth)acrylic resin, the soft material having at least one glass transition temperature (Tg) of -30°C or lower, and the glycerin fatty acid ester in the (meth)acrylic resin composition is taken as 100 mass%, the content of the (meth)acrylic resin is in the range of 35 mass% or more and 84 mass% or less, the content of the soft material having at least one glass transition temperature (Tg) of -30°C or lower is in the range of 15 mass% or more and 60 mass% or less, and the content of the glycerin fatty acid ester is in the range of 1 mass% or more and 15 mass% or less.

[0012] First, the components that can be contained in the (meth)acrylic resin composition of the present embodiment will be specifically described.

[0013] <(Meth)acrylic resin> Examples of the (meth)acrylic resin that can be used in the (meth)acrylic resin composition of the present embodiment include homopolymers of (meth)acrylic monomers such as (meth)acrylic acid esters and (meth)acrylonitrile, copolymers of two or more monomers, and copolymers of (meth)acrylic monomers and other monomers.

[0014] In this specification, the term "(meth)acrylic" means "acrylic" or "methacrylic".

[0015] As the (meth)acrylic resin, it is preferable to use a methacrylic resin because of its excellent hardness, weather resistance, and transparency. The methacrylic resin is a polymer obtained by polymerizing a monomer mainly composed of a methacrylic acid ester (alkyl methacrylate).

[0016] Examples of (meth)acrylic resins include homopolymers of methacrylic acid esters, which are monomers (polyalkyl methacrylates), copolymers of methacrylic acid esters, and copolymers of 50% by mass or more of methacrylic acid esters and 50% by mass or less of monomers other than methacrylic acid esters.

[0017] When the (meth)acrylic resin is a copolymer of a methacrylic acid ester and a monomer other than the methacrylic acid ester, it is preferable that the methacrylic acid ester is 70 mass% or more and the monomer other than the methacrylic acid ester is 30 mass% or less, relative to 100 mass% of the total amount of monomers, and it is more preferable that the methacrylic acid ester is 90 mass% or more and the monomer other than the methacrylic acid ester is 10 mass% or less.

[0018] Examples of monomers other than methacrylic acid esters include acrylic acid esters and monofunctional monomers having one polymerizable carbon-carbon double bond in the molecule.

[0019] Examples of such monofunctional monomers include styrene-based monomers such as styrene, α-methylstyrene, and vinyltoluene; alkenyl cyanides such as acrylonitrile and methacrylonitrile; acrylic acid; methacrylic acid; maleic anhydride; and N-substituted maleimides such as phenylmaleimide, cyclohexylmaleimide, and methylmaleimide. In order to improve heat resistance, a lactone ring structure, a glutaric anhydride structure, or a glutarimide structure may be introduced into the main chain (main skeleton) of the (meth)acrylic resin.

[0020] More specifically, the (meth)acrylic resin is preferably a (meth)acrylic resin that satisfies the following condition (a1) or condition (a2). (a1) Homopolymer of methyl methacrylate (a2) A copolymer containing 50 to 99.9% by mass of a structural unit derived from methyl methacrylate and 0.1 to 50% by mass of at least one structural unit derived from a (meth)acrylic acid ester represented by the following formula (1):

[0021] [ka]

[0022] In the formula (1), R1 represents a hydrogen atom or a methyl group, and when R1 is a hydrogen atom, R2 represents an alkyl group having 1 to 8 carbon atoms, and when R1 is a methyl group, R2 represents an alkyl group having 2 to 8 carbon atoms.

[0023] In the above condition (a2), it is preferable that the total amount of the structural units derived from methyl methacrylate and at least one structural unit derived from the (meth)acrylic acid ester represented by the above formula (1) is 100 mass %.

[0024] In the formula (1), when R1 is a hydrogen atom, examples of the alkyl group having 1 to 8 carbon atoms represented by R2 include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, a hexyl group, a heptyl group, and an octyl group. In the formula (1), when R1 is a methyl group, examples of the alkyl group having 2 to 8 carbon atoms represented by R2 include an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, a hexyl group, a heptyl group, and an octyl group.

[0025] The (meth)acrylic acid ester represented by the formula (1) is preferably methyl acrylate or ethyl acrylate, and more preferably methyl acrylate.

[0026] In the present embodiment, the (meth)acrylic resin has a melt mass flow rate (MFR) at 230°C measured under a load of 3.8 kg in accordance with a method in accordance with JIS K 7210 of usually 0.1 to 30 g / 10 min., and from the viewpoint of improving the strength of a base material, which is a molded product obtained by molding the (meth)acrylic resin composition, and also improving its moldability, the MFR is preferably 0.2 to 20 g / 10 min., and more preferably 0.5 to 15 g / 10 min.

[0027] In the present embodiment, the (meth)acrylic resin has a weight average molecular weight (Mw) determined by GPC measurement, from the viewpoints of improving transparency when exposed to conditions of, for example, 60°C and a relative humidity of 90%, and also improving moldability, of preferably 30,000 to 300,000, more preferably 40,000 to 250,000, and even more preferably 50,000 to 200,000.

[0028] In this embodiment, from the viewpoint of improving heat resistance, the (meth)acrylic resin preferably has a Vicat softening temperature (VST) measured according to a method in accordance with JIS K 7206 of 90° C. or more, more preferably 100° C. or more, and even more preferably 102° C. or more. The VST of the (meth)acrylic resin can be appropriately set by adjusting the types and ratios of the monomers and further the molecular weight of the (meth)acrylic resin.

[0029] The (meth)acrylic resin can be prepared (synthesized) by polymerizing the monomers already described by any suitable conventional method such as suspension polymerization or bulk polymerization. In the preparation, for example, any suitable conventional chain transfer agent can be further added to adjust the properties of the (meth)acrylic resin, such as MFR, Mw, and VST, to preferred ranges. The amount of the chain transfer agent to be added can be appropriately determined depending on the type and ratio of the selected monomers, and further the desired properties.

[0030] <Soft material with at least one glass transition temperature (Tg) below -30°C> The (meth)acrylic resin composition of the present embodiment includes a soft material having at least one glass transition temperature (Tg) of −30° C. or lower. Specifically, the term “soft material” used herein refers to a material that can be deformed by application of pressure at room temperature.

[0031] In this embodiment, the glass transition temperature of the "soft material having at least one glass transition temperature (Tg) of -30°C or lower" is preferably -30°C or lower, more preferably -35°C or lower, and even more preferably -40°C or higher.

[0032] In this embodiment, the "glass transition temperature (Tg)" can be measured in accordance with, for example, JIS-K7121. Specifically, the glass transition temperature (Tg) can be measured according to the measurement method described in paragraph

[0061] of JP-A-2003-342388.

[0033] The glass transition temperature can be measured using any suitable conventional measuring device (for example, a differential scanning calorimeter "DSC7020" manufactured by Hitachi High-Tech Science Corporation).

[0034] Specifically, after a soft material is completely melted under an inert gas atmosphere, the measurement can be performed based on a DSC curve obtained according to a predetermined temperature profile.

[0035] Examples of the "soft material having at least one glass transition temperature (Tg) of -30°C or lower" that can be used in the (meth)acrylic resin composition of this embodiment include polybutadiene, a styrene-ethene-butene-styrene block polymer, and an acrylic soft material.

[0036] As the "soft material having at least one glass transition temperature (Tg) of -30°C or less" that can be used in the (meth)acrylic resin composition of this embodiment, from the viewpoint of effectively re-bleeding the active ingredient glycerin fatty acid ester multiple times, it is preferable to use polybutadiene, a styrene-ethene-butene-styrene block polymer, and an acrylic soft material, and it is more preferable to use an acrylic soft material.

[0037] In this embodiment, it is preferable to use an acrylic block copolymer as the acrylic soft material from the viewpoint of the above-described action and effect, such as the multiple rebleeding of glycerin fatty acid ester, and further from the viewpoint of availability.

[0038] Here, an acrylic block copolymer that can be suitably applied to the (meth)acrylic resin composition of this embodiment will be described.

[0039] In this embodiment, the acrylic block copolymer is a block copolymer containing a methacrylic acid ester polymer block (b1) mainly containing methacrylic acid ester units and an acrylic acid ester polymer block (b2) mainly containing acrylic acid ester units. The acrylic block copolymer may contain only one methacrylic acid ester polymer block (b1), or may contain two or more methacrylic acid ester polymer blocks (b1). The acrylic block copolymer (B) may contain only one acrylic acid ester polymer block (b2), or may contain two or more acrylic acid ester polymer blocks (b2).

[0040] In the acrylic block copolymer, the mode of bonding between the methacrylic acid ester polymer block (b1) and the acrylic acid ester polymer block (b2) is not particularly limited.

[0041] Examples of the bonding form in the acrylic block copolymer include a diblock copolymer having a structure represented by the formula (b1)-(b2), in which one end of the methacrylic acid ester polymer block (b1) is bonded to one end of the acrylic acid ester polymer block (b2); a triblock copolymer having a structure represented by the formula (b2)-(b1)-(b2), in which one end of the acrylic acid ester polymer block (b2) is bonded to each of both ends of the methacrylic acid ester polymer block (b1); and a triblock copolymer having a structure represented by the formula (b1)-(b2)-(b1), in which one end of the methacrylic acid ester polymer block (b1) is bonded to each of both ends of the acrylic acid ester polymer block (b2).

[0042] Examples of the bonding form in the acrylic block copolymer include a block copolymer having a radial configuration in which a plurality of structures represented by "(b1)-(b2)" are bonded together (a structure represented by [(b1)-(b2)-]nX (n is an integer of 2 or more, and X is a residue of the coupling agent used, and the same applies below)); a block copolymer having a radial configuration in which a plurality of structures represented by "(b2)-(b1)" are bonded together (a structure represented by [(b2)-(b1)-]nX); a block copolymer having a radial configuration in which a plurality of structures represented by "(b1)-(b2)-(b1)" are bonded together (a structure represented by [(b1)-(b2)-(b1)-]nX); a block copolymer having a radial configuration in which a plurality of structures represented by "(b2)-(b1)-(b2)" are bonded together (a structure represented by [(b2)-(b1)-(b2)-]nX), and a block copolymer having a branched structure.

[0043] In this embodiment, the acrylic block copolymer is preferably a diblock copolymer, triblock copolymer, or star block copolymer as already explained, and more preferably a diblock copolymer having a structure represented by the formula (b1)-(b2), a triblock copolymer having a structure represented by the formula (b1)-(b2)-(b1), a star block copolymer having a structure represented by the formula [(b1)-(b2)-]nX, or a star block copolymer having a structure represented by (b1)-(b2)-(b1)-]nX. It is even more preferable to use an acrylic block copolymer having a structure in which one methacrylic acid ester polymer block (b1) is bonded to each of both terminal sides of the acrylic acid ester polymer block (b2), i.e., a structure represented by the formula (b1)-(b2)-(b1).

[0044] In the present embodiment, from the viewpoint of ensuring good transparency in the (meth)acrylic resin composition and further in the base material, the acrylic block copolymer is preferably a block copolymer in which the content of the methacrylic acid ester polymer block is in the range of 30% by mass or more and 60% by mass or less, and the content of the acrylic acid ester polymer block is in the range of 40% by mass or more and 70% by mass or less.

[0045] In the acrylic block copolymer, the methacrylic acid ester copolymer block (b1) is a copolymer block mainly composed of structural units derived from a methacrylic acid ester. The proportion of structural units derived from a methacrylic acid ester in the methacrylic acid ester polymer block (b1) is preferably 80% by mass or more, more preferably 90% by mass or more, even more preferably 95% by mass or more, and particularly preferably 98% by mass or more.

[0046] Examples of methacrylate esters, which are monomers that can constitute the methacrylate ester copolymer block of this embodiment, include methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, sec-butyl methacrylate, tert-butyl methacrylate, amyl methacrylate, isoamyl methacrylate, n-hexyl methacrylate, cyclohexyl methacrylate, 2-ethylhexyl methacrylate, pentadecyl methacrylate, dodecyl methacrylate, isobornyl methacrylate, phenyl methacrylate, benzyl methacrylate, phenoxyethyl methacrylate, 2-hydroxyethyl methacrylate, 2-methoxyethyl methacrylate, glycidyl methacrylate, and allyl methacrylate. Among these, from the viewpoint of improving transparency and further heat resistance, methacrylic acid alkyl esters such as methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, tert-butyl methacrylate, cyclohexyl methacrylate, and isobornyl methacrylate are preferred, and methyl methacrylate is more preferred. In synthesizing the methacrylic acid ester copolymer block (b1), these methacrylic acid esters may be polymerized singly or in combination of two or more.

[0047] The methacrylic acid ester polymer block (b1) may contain a constituent unit derived from a monomer other than a methacrylic acid ester, so long as the object and the effect of the present invention are not impaired. The proportion of the constituent unit derived from a monomer other than a methacrylic acid ester that can be contained in the methacrylic acid ester polymer block (b1) is preferably 20% by mass or less, more preferably 10% by mass or less, further preferably 5% by mass or less, and particularly preferably 2% by mass or less.

[0048] Examples of monomers other than methacrylic acid esters that can constitute the methacrylic acid ester copolymer block of this embodiment include acrylic acid esters, unsaturated carboxylic acids, aromatic vinyl compounds, olefins, conjugated dienes, acrylonitrile, methacrylonitrile, acrylamide, methacrylamide, vinyl acetate, vinylpyridine, vinyl ketone, vinyl chloride, vinylidene chloride, and vinylidene fluoride. The methacrylic acid ester polymer block (b1) can be formed by copolymerizing one or more of these monomers other than methacrylic acid esters together with the above-mentioned methacrylic acid esters.

[0049] The methacrylic acid ester polymer block (b1) is preferably composed of a polymer having a refractive index in the range of 1.485 to 1.495, from the viewpoint of enhancing the transparency of the (meth)acrylic resin composition and further the preform.

[0050] The weight average molecular weight of the methacrylic acid ester polymer block (b1) is preferably 5,000 or more and 150,000 or less, more preferably 8,000 or more and 120,000 or less, and further preferably 12,000 or more and 100,000 or less.

[0051] When the acrylic block copolymer contains a plurality of methacrylic acid ester polymer blocks (b1), the composition ratio and molecular weight of the structural units (monomers) constituting the methacrylic acid ester polymer blocks (b1) may be the same or different.

[0052] The maximum weight average molecular weight Mw(b1) of the methacrylic acid ester polymer block (b1) is preferably 12,000 or more and 150,000 or less, more preferably 15,000 or more and 120,000 or less, and even more preferably 20,000 or more and 100,000 or less. Here, when only one methacrylic acid ester polymer block (b1) is contained in the acrylic block copolymer, the weight average molecular weight of the methacrylic acid ester polymer block (b1) is Mw(b1). When two or more methacrylic acid ester polymer blocks (b1) are contained in the acrylic block copolymer and the weight average molecular weights of the two or more methacrylic acid ester polymer blocks (b1) are the same, the weight average molecular weight is Mw(b1).

[0053] The content (ratio) of the methacrylic acid ester polymer block (b1) in the acrylic block copolymer is preferably 10% by mass or more and 60% by mass or less, more preferably 20% by mass or more and 55% by mass or less, from the viewpoint of improving transparency, flexibility, processability, and surface smoothness. If the ratio of the methacrylic acid ester polymer block (b1) in the acrylic block copolymer is within the above range, the properties such as transparency, flexibility, bending resistance, impact resistance, and flexibility of the (meth)acrylic resin composition and the preform can be improved. When the acrylic block copolymer contains two or more methacrylic acid ester polymer blocks (b1), the above ratio may be calculated based on the total mass of all the methacrylic acid ester polymer blocks (b1).

[0054] The acrylic acid ester polymer block (b2) is a block copolymer mainly composed of structural units derived from an acrylic acid ester monomer. The proportion of structural units derived from an acrylic acid ester in the acrylic acid ester polymer block (b2) is preferably 45% by mass or more, more preferably 50% by mass or more, even more preferably 60% by mass or more, and particularly preferably 90% by mass or more.

[0055] Examples of acrylic acid esters include methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, sec-butyl acrylate, tert-butyl acrylate, amyl acrylate, isoamyl acrylate, n-hexyl acrylate, cyclohexyl acrylate, 2-ethylhexyl acrylate, pentadecyl acrylate, dodecyl acrylate, isobornyl acrylate, phenyl acrylate, benzyl acrylate, phenoxyethyl acrylate, 2-hydroxyethyl acrylate, 2-methoxyethyl acrylate, glycidyl acrylate, allyl acrylate, etc. The acrylic acid ester polymer block (b2) can be formed by polymerizing one or more of these acrylic acid esters in combination according to a conventional method.

[0056] The acrylic acid ester polymer block (b2) may contain structural units derived from monomers other than acrylic acid esters, so long as the purpose and effects of the present invention are not impaired. The proportion of structural units derived from monomers other than acrylic acid esters contained in the acrylic acid ester polymer block (b2) is preferably 55% by mass or less, more preferably 50% by mass or less, even more preferably 40% by mass or less, and particularly preferably 10% by mass or less.

[0057] Examples of monomers other than acrylic acid esters include methacrylic acid esters, unsaturated carboxylic acids, aromatic vinyl compounds, olefins, conjugated dienes, acrylonitrile, methacrylonitrile, acrylamide, methacrylamide, vinyl acetate, vinylpyridine, vinyl ketone, vinyl chloride, vinylidene chloride, vinylidene fluoride, etc. The acrylic acid ester polymer block (b2) can be formed by copolymerizing one or more of these monomers other than acrylic acid esters together with the acrylic acid ester monomer.

[0058] As long as the object and effect of the present invention are not impaired, the acrylic block copolymer may further contain another polymer block (b3) derived from a monomer other than acrylic acid ester and methacrylic acid ester as a polymer block other than the methacrylic acid ester polymer block (b1) and the acrylic acid ester copolymer block (b2). The bonding mode between the other polymer block (b3) and the methacrylic acid ester polymer block (b1) and the acrylic acid ester polymer block (b2) is not particularly limited. Examples of the bonding mode between the other polymer block (b3) and the methacrylic acid ester polymer block (b1) and the acrylic acid ester polymer block (b2) include the modes represented by the formula: (b1)-((b2)-(b1))n-(b3) and the formula: (b3)-(b1)-((b2)-(b1)n-(b3) (wherein n represents an integer of 1 to 20).

[0059] Other monomers that can constitute the polymer block (b3) include, for example, olefins such as ethylene, propylene, 1-butene, isobutylene, and 1-octene; conjugated diene compounds such as 1,3-butadiene, isoprene, and myrcene; aromatic vinyl compounds such as styrene, α-methylstyrene, p-methylstyrene, and m-methylstyrene; vinyl acetate, vinylpyridine, acrylonitrile, methacrylonitrile, vinyl ketone, vinyl chloride, vinylidene chloride, vinylidene fluoride, acrylamide, methacrylamide, ε-caprolactone, and valerolactone.

[0060] The method for producing the acrylic block copolymer is not particularly limited, and any suitable conventionally known production method can be adopted. Examples of the method for producing the acrylic block copolymer include the living polymerization method (living polymerization method) of the monomers that can constitute various polymer blocks as already described. Examples of such living polymerization methods include a method of anionically polymerizing an organic alkali metal compound as a polymerization initiator in the presence of a mineral acid salt such as an alkali metal or alkaline earth metal salt, a method of anionically polymerizing an organic alkali metal compound as a polymerization initiator in the presence of an organoaluminum compound, a method of polymerizing an organic rare earth metal complex as a polymerization initiator, and a method of radically polymerizing an α-halogenated ester compound as an initiator in the presence of a copper compound. In addition, a method of producing a mixture containing an acrylic block copolymer by polymerizing each block using a polyvalent radical polymerization initiator or a polyvalent radical chain transfer agent can be exemplified. Among these methods for producing the acrylic block copolymer, it is particularly preferable to adopt a method of anionically polymerizing an organic alkali metal compound as a polymerization initiator in the presence of an organoaluminum compound, because the acrylic block copolymer can be obtained with high purity, the molecular weight and composition ratio can be easily controlled, and it is economical.

[0061] In the present embodiment, the acrylic block copolymer may be a commercially available product. Examples of commercially available acrylic block copolymers that can be suitably applied to the present embodiment include LA4285 (manufactured by Kuraray Co., Ltd., PMMA ratio: 50%, Tg: -45.7°C) and LA2270 (manufactured by Kuraray Co., Ltd., PMMA ratio: 40%, Tg: -45°C).

[0062] <Glycerol fatty acid ester> Glycerol fatty acid esters are known to have antiviral properties that can inactivate the new coronavirus (SARS-CoV2 virus).

[0063] In this embodiment, the glycerin fatty acid ester has the function of exerting antiviral properties particularly against the new coronavirus, and further has the function of suppressing the generation of static electricity and even the adhesion of dust by seeping out (bleeding) onto the surface of the molded body and covering the surface.

[0064] In this embodiment, the glycerin fatty acid ester is a glycerin fatty acid ester having an HLB value in the range of 5 to 12. The HLB value is preferably 5.4 or more, and more preferably 9.4 or less, from the viewpoint of recovery of antiviral properties, static electricity generation, and effective suppression of dust adhesion by re-bleeding the glycerin fatty acid ester each time it is bled onto the surface and wiped off multiple times. The HLB value is preferably in the range of 5 to 9.4 or in the range of 5.4 to 12, and more preferably in the range of 5.4 to 9.4.

[0065] Here, the HLB (Hydrophilic Lipophilic Balance) value is a parameter that can take a value from 0 to 20, and the closer to 0, the higher the lipophilicity (hydrophobicity), and the closer to 20, the higher the hydrophilicity. A compound such as paraffin that does not have a hydrophilic group and has only a hydrophobic group has an HLB value of 0, a compound such as polyethylene glycol that does not have a hydrophobic group and has only a hydrophilic group has an HLB value of 20, and a compound that has both a hydrophilic group and a hydrophobic group in one molecule has a value between 1 and 20. Therefore, the greater the hydrophilicity of the hydrophilic group relative to the hydrophobicity of the hydrophobic group portion in the molecule, the greater the HLB value and the higher the water solubility, and the smaller the hydrophilicity of the hydrophilic group relative to the hydrophobicity of the hydrophobic group portion in the molecule, the smaller the HLB value and the lower the water solubility.

[0066] The HLB value of a given compound (molecule) can be calculated, for example, by the Griffin method using the following formula (2). HLB value = 20 × sum of chemical formula weights of hydrophilic parts / sum of chemical formula weights of hydrophobic parts (2)

[0067] In this embodiment, the number of carbon atoms in the alkyl chain of the glycerin fatty acid ester is not particularly limited. Specific examples include caprylic acid, capric acid, lauric acid, myristic acid, stearic acid, and oleic acid. Examples of fatty acid esters constituting the glycerin fatty acid ester include mono-fatty acid esters, di-fatty acid esters, and tri-fatty acid esters. Among these, the fatty acid ester is preferably a mono-fatty acid ester or a di-fatty acid ester.

[0068] Examples of glycerin that can be used in the present embodiment and can form the glycerin fatty acid ester include monoglycerin, diglycerin, triglycerin, tetraglycerin, pentaglycerin, and decaglycerin. Among these, the glycerin that can form the glycerin fatty acid ester is preferably monoglycerin, diglycerin, or even decaglycerin, and more preferably diglycerin.

[0069] Specific examples of glycerin fatty acid esters include monoglycerin monocaprylate (HLB value 7.0), monoglycerin monocaprate (HLB value 6.8), monoglycerin monolaurate (HLB value 5.4), monoglycerin monomyristate, diglycerin monocaprylate, diglycerin monocaprate, diglycerin monolaurate (HLB value 9.4), diglycerin monomyristate, triglycerin monocaprylate, triglycerin monocaprate, triglycerin monolaurate, triglycerin monomyristate, tetraglycerin monocaprylate, tetraglycerin monocaprate, tetraglycerin monolaurate, tetra ... Examples of such glycerin monolaurate include serine monolaurate, tetraglycerin monomyristate, pentaglycerin monocaprylate, pentaglycerin monocaprate, pentaglycerin monolaurate, pentaglycerin monomyristate, and decaglycerin monooleate (decaglycerin oleate) (HLB value 12). Among these, glycerin saturated fatty acid esters such as monoglycerin monocaprate (HLB value 6.8), monoglycerin monolaurate (HLB value 5.4), and diglycerin monolaurate (HLB value 9.4) are preferred, and diglycerin monolaurate (HLB value 9.4), which is a diglycerin mono fatty acid ester, is more preferred.

[0070] The HLB value of the glycerin fatty acid ester can be determined by referring to values ​​disclosed in conventionally known documents. In addition, the glycerin fatty acid ester may be, for example, a commercially available product.

[0071] <(Meth)acrylic resin composition> (1) (Meth)acrylic resin In the (meth)acrylic resin composition of the present embodiment, the content of the (meth)acrylic resin is usually more than 20% by mass and less than 85% by mass, when the total content of the already-described (meth)acrylic resin, the soft material having at least one glass transition temperature (Tg) of -30°C or less, and the glycerin fatty acid ester is taken as 100% by mass. From the viewpoints of maintaining antiviral properties, effectively suppressing the generation of static electricity, and further suppressing the adhesion of dust, the content of the (meth)acrylic resin is preferably 42% by mass or more, more preferably 45% by mass or more, even more preferably 47.5% by mass or more, preferably 55% by mass or less, and more preferably 70% by mass or less, preferably in the range of 42% by mass or more and 84% by mass or less, more preferably in the range of 35% by mass or more and 84% by mass or less, even more preferably in the range of 42% by mass or more and 70% by mass or less, and particularly preferably in the range of 47.5% by mass or more and 70% by mass or less.

[0072] (2) A soft material that has at least one glass transition temperature (Tg) below -30°C In the (meth)acrylic resin composition of the present embodiment, the content of the soft material having at least one glass transition temperature (Tg) of -30°C or less is usually more than 10% by mass and less than 75% by mass, when the total content of the already-described (meth)acrylic resin, the soft material having at least one glass transition temperature (Tg) of -30°C or less, and the glycerin fatty acid ester is taken as 100% by mass. From the viewpoints of maintaining antiviral properties, effectively suppressing the generation of static electricity and adhesion of dust, and particularly ensuring good transparency, the content may be in the range of 15% by mass or more and 60% by mass or less, preferably 25% by mass or more, preferably 50% by mass or less, and more preferably 40% by mass or less. From the viewpoints of particularly improving transparency, the content is preferably in the range of 25% by mass or more and 50% by mass or less, and more preferably 40% by mass or more and 50% by mass or less.

[0073] (3) Glycerol fatty acid esters In the (meth)acrylic resin composition of the present embodiment, the content of the glycerin fatty acid ester is usually more than 0.5% by mass and less than 15% by mass, when the total content of the already-described (meth)acrylic resin, the soft material having at least one glass transition temperature (Tg) of -30°C or less, and the glycerin fatty acid ester is taken as 100% by mass. From the viewpoints of maintaining the antiviral properties, effectively suppressing the generation of static electricity and the adhesion of dust, and in particular recovering the antiviral properties, the generation of static electricity and the effective suppression of the adhesion of dust by multiple re-bleeding, the content may be in the range of 1.0% by mass or more and 15% by mass or less, preferably 2.5% by mass or more, preferably 8% by mass or less, and more preferably 5% by mass or less. From the viewpoint of effectively maintaining the antiviral properties, the content is preferably in the range of 2.5% by mass or more and 5.0% by mass or less, and from the viewpoint of ensuring good transparency of the (meth)acrylic resin composition and the base material, the content is preferably 1.0% by mass or more and 10% by mass or less.

[0074] In the (meth)acrylic resin composition of the present embodiment, by blending the (meth)acrylic resin, the soft material having at least one glass transition temperature (Tg) of -30°C or less, and the glycerin fatty acid ester in the above-mentioned ratio, antiviral properties and further the generation of static electricity on the surface of the base material and thus the adhesion of dust can be effectively suppressed. In particular, the glycerin fatty acid ester that imparts antiviral properties is bled to the surface. Furthermore, even if the glycerin fatty acid ester that has bled to the surface of the base material is wiped off multiple times, for example, by an alcohol disinfection treatment using ethanol, the content of the glycerin fatty acid ester, which is particularly an active ingredient, can be increased. Therefore, the glycerin fatty acid ester can be repeatedly re-bleeded each time it is wiped off the surface, and antiviral properties and further the generation of static electricity and thus the adhesion of dust can be effectively suppressed. In addition, good transparency can be imparted if necessary, and these properties can be maintained for a predetermined period of time.

[0075] The amount of other resins that may be contained in the (meth)acrylic resin composition of this embodiment is preferably 20 mass % or less, more preferably 10 mass % or less, and even more preferably 5 mass % or less, relative to the total amount (100 mass %) of the (meth)acrylic resin composition.

[0076] Examples of other resins that may be contained in the (meth)acrylic resin composition of the present embodiment include polycarbonate resins, polyamide resins, acrylonitrile-styrene copolymers, methyl methacrylate-styrene copolymers, and polyethylene terephthalate.

[0077] (4) Other ingredients The (meth)acrylic resin composition of the present embodiment may further contain other components that can be generally used in (meth)acrylic resin compositions, provided that the effects of the present invention are not impaired.

[0078] Examples of other components that may be contained in the (meth)acrylic resin composition of the present embodiment include crosslinked rubber particles, an ultraviolet absorber, a slipping agent, an antioxidant, a release agent, and an antistatic agent.

[0079] Examples of the crosslinked rubber particles which are other components include multi-layered rubber particles which have at least a core and a coating layer covering the core, and at least one of the core and the coating layer is formed from a material having a structural unit derived from a polyfunctional monomer having two or more carbon-carbon unsaturated bonds.

[0080] Examples of the ultraviolet absorbing agent which is another component include a benzophenone-based ultraviolet absorbing agent, a cyanoacrylate-based ultraviolet absorbing agent, a benzotriazole-based ultraviolet absorbing agent, a malonic acid ester-based ultraviolet absorbing agent, and an oxalanilide-based ultraviolet absorbing agent.

[0081] Examples of the slipping agent that is another component include silicone oil and polysiloxane compounds.

[0082] Examples of the antioxidant that is another component include a phenol-based antioxidant, a sulfur-based antioxidant, and a phosphorus-based antioxidant.

[0083] Examples of the release agent that is another component include higher fatty acid esters other than the "glycerin fatty acid ester" already explained, higher aliphatic alcohols, higher fatty acids, higher fatty acid amides, higher fatty acid metal salts, and fatty acid derivatives.

[0084] Examples of the antistatic agent that is another component include conductive inorganic particles, tertiary amines, quaternary ammonium salts, cationic acrylic acid ester derivatives, and cationic vinyl ether derivatives.

[0085] <Method of producing (meth)acrylic resin composition> The (meth)acrylic resin composition of the present embodiment can be produced (prepared) by carrying out a kneading step using any suitable conventionally known device and conditions to mix the (meth)acrylic resin, the soft material having at least one glass transition temperature (Tg) of −30° C. or lower, the glycerin fatty acid ester, and other desired components, as already described above.

[0086] In this embodiment, the temperature conditions in the (melt) kneading step are not particularly limited. The temperature conditions can be any suitable conditions taking into consideration the selected components, their amounts, properties, etc. In the melt kneading step, for example, the temperature from the raw material inlet to the outlet of the extruder may be set to 180°C to 260°C.

[0087] As the equipment that can be used in the kneading step, any suitable mixer or kneader known in the art can be used. Specific examples of such equipment include a single-screw kneader, a twin-screw kneader, a multi-screw extruder, a Henschel mixer, a Banbury mixer, a kneader, and a roll mill. In addition, when it is necessary to increase the rotation speed in the kneading step, for example, a high-shear processing device may be used.

[0088] <Materials> The (meth)acrylic resin composition of the present embodiment can be molded into a base material having a desired shape by any suitable conventional molding method (the method for manufacturing the base material will be described later).

[0089] According to the base material of this embodiment, the glycerin fatty acid ester already explained bleeds onto its surface, and the glycerin fatty acid ester exerts antiviral properties as an active ingredient, and furthermore, can effectively suppress the generation of static electricity on the surface of the base material and the adhesion of dust. Moreover, even if the glycerin fatty acid ester is wiped off, the glycerin fatty acid ester can be re-bleeded multiple times, so that the base material can be used as a base material in which the antiviral properties, the effect of suppressing the generation of static electricity and the adhesion of dust can be restored (maintained) multiple times.

[0090] Here, the preform refers to a part, member, or even the final product itself that is given a predetermined shape by applying a predetermined heat or force to a material such as a resin composition, rubber, glass, or metal. That is, the preform having antiviral properties of this embodiment is a molded product that is formed into a predetermined shape by molding the (meth)acrylic resin composition described above.

[0091] In this embodiment, the shape, thickness, and other dimensions of the preform that can be produced are not particularly limited. In this embodiment, the preform is preferably a sheet (layer, plate) formed from the (meth)acrylic resin composition described above.

[0092] In this embodiment, a laminate sheet may be formed containing one or more layers of the (meth)acrylic resin composition formed from the (meth)acrylic resin composition as described above. That is, the base material of this embodiment includes a laminate sheet (laminate) containing a layer containing the (meth)acrylic resin composition as described above.

[0093] The preform molded from the (meth)acrylic resin composition of the present embodiment has antiviral properties, particularly against the novel coronavirus, and can effectively suppress the generation of static electricity on the surface of the preform and therefore the adhesion of dust. Therefore, it can be suitably used as a preform contained in equipment, tools, etc. that may come into contact with the human body.

[0094] The base material molded from the (meth)acrylic resin composition of the present embodiment has the properties as already described, and therefore, when transparency is not required for the application, it can be suitably applied to components that will inevitably come into contact with the human body frequently during use, such as handrails, door handles, containers, container lids, and wall materials.

[0095] Furthermore, when transparency is required for the application, the film can be suitably used as a screen (that can be placed on a desk) for separating adjacent or facing customers in a store, etc., or adjacent or facing attendees in a meeting, etc., a partition, a cover material for covering product samples in a vending machine, a cover material for lighting, and further a component for a display panel such as a protective sheet placed on the outermost surface of a touch sensor panel, and a component for a meter panel of a vehicle such as an automobile or motorcycle.

[0096] (1) Seat The thickness of the sheet, which is a base material formed from the (meth)acrylic resin composition of the present embodiment, may be appropriately selected depending on the application to which it is applied, and is not particularly limited. In the present embodiment, the thickness of the sheet is preferably 100 to 4000 μm, more preferably 200 to 3000 μm, for example, when applied to a screen or partition.

[0097] (2) Laminated sheet In this embodiment, the laminate sheet includes at least one layer of the (meth)acrylic resin composition, which is a sheet formed from the (meth)acrylic resin composition described above. The layer of the (meth)acrylic resin composition is preferably provided so as to cover at least the surface that is expected to come into contact with the human body.

[0098] In the present embodiment, from the viewpoint of improving hardness and strength, the laminate sheet preferably further includes a base layer, and layers of the (meth)acrylic resin composition are provided on both the first and second main surfaces facing each other in the thickness direction of the base layer so as to sandwich the base layer. The base layer may include not only one layer, but also two or more layers.

[0099] Here, the thickness of the base layer can be any suitable thickness taking into consideration the application of the laminate sheet. When the laminate sheet is applied to, for example, a screen or a partition, the thickness of the base layer is preferably 500 to 4000 μm, more preferably 1000 to 3000 μm, from the viewpoint of maintaining the shape.

[0100] The material of the substrate layer is not particularly limited and may be selected from any suitable conventionally known materials according to the application of the laminate sheet. Examples of the material of the substrate layer include (meth)acrylic resin, styrene resin, MS resin, polycarbonate resin, etc. In particular, when transparency is required for the application, the transparency of the entire laminate sheet can be increased by combining with a highly transparent substrate layer, so that it is preferable to use a transparent material as the material of the substrate layer.

[0101] In addition, when the laminate sheet is, for example, a screen or partition intended for use facing each other and transparency (visible light transmittance) is particularly required, the material of the base layer is preferably a (meth)acrylic resin composition that may have a composition and blending ratio different from the (meth)acrylic resin composition of this embodiment. Here, from the viewpoint of ensuring transparency, the material of the base layer is preferably composed of only a (meth)acrylic resin, and may be a (meth)acrylic resin composition further containing another resin such as vinylidene fluoride resin.

[0102] <Material manufacturing method> The method for producing the preform of the present embodiment is not particularly limited. For example, the method for producing the preform of the present embodiment may be a method for molding the (meth)acrylic resin composition described above using any suitable conventional molding machine.

[0103] Examples of the method for producing the preform of the present embodiment include extrusion molding and injection molding. When the preform is to be formed into a preform having a more complicated shape, for example, an injection molding method may be used in which an injection molding machine is used as a molding machine and a (meth)acrylic resin composition is injected into a mold of the molding machine to form the preform.

[0104] In the case of producing the sheet or laminated sheet as described above, it is preferable to use an extrusion molding method. In particular, in the case of producing a laminated sheet in which the material of the base layer is a resin composition to which an extrusion molding method, such as a (meth)acrylic resin composition, can be applied, the base layer and the layer of the (meth)acrylic resin composition containing the (meth)acrylic resin composition of the present embodiment can be molded simultaneously, and the laminated sheet can be produced integrally and more simply.

[0105] The method for producing the base material of this embodiment will be described below by taking an extrusion molding method as an example.

[0106] The method for producing a shaped material according to the present embodiment includes a step of preparing a (meth)acrylic resin composition and a step of extruding the prepared (meth)acrylic resin composition to produce a shaped material. Each step will be specifically described below.

[0107] (1) A step of preparing a (meth)acrylic resin composition This step is a step of preparing a (meth)acrylic resin composition to be fed to an extruder.

[0108] In this embodiment, the properties of the methacrylic resin composition fed to the extrusion molding machine are not particularly limited. The shape, size, etc. of the (meth)acrylic resin composition fed to the extrusion molding machine may be set within any suitable range, taking into consideration the extrusion molding machine used, the conditions applied, etc.

[0109] (2) A step of extruding the (meth)acrylic resin composition to obtain a base material. This step is a step in which the (meth)acrylic resin composition is molded by an extrusion molding machine to form a base material.

[0110] Specifically, a sheet, which is an example of the base material of this embodiment, can be produced by extruding a molten (meth)acrylic resin composition from the die of an extrusion molding machine and molding it with the die lips in a conventional manner.

[0111] A laminate sheet, which is an example of the base material of the present embodiment, for example, has a two-kind three-layer structure in which the above-mentioned sheet is used as a layer of (meth)acrylic resin composition and is provided on both a first main surface and a second main surface opposing each other in the thickness direction of a base layer so as to sandwich the base layer (a laminate sheet laminated in the order of a layer of (meth)acrylic resin composition / base layer / layer of (meth)acrylic resin composition), can be produced, for example, as follows.

[0112] First, a melt of the (meth)acrylic resin composition of the present embodiment already described and a melt of the resin composition which is the material of the substrate layer are each prepared.

[0113] Next, for example, using an extrusion molding machine equipped with a multi-manifold die, a resin composition that is a molten material for the base layer is extruded from the middle die lip, and at the same time, the molten (meth)acrylic resin composition of this embodiment is extruded from the upper and lower die lips. The extruded molded product is cooled, as necessary, using any suitable cooling roll known in the art, or further molded using other rolls such as a conveying roll, to produce a laminate sheet that is a laminate having a two-kind three-layer structure including a layer (sheet) of the (meth)acrylic resin composition of this embodiment, which is a layer of the (meth)acrylic resin composition, on both the first and second main surfaces of the base layer molded in the middle, so as to sandwich the base layer.

[0114] In producing the laminate sheet of this embodiment, the temperature conditions for forming the layer of the (meth)acrylic resin composition by extrusion molding can be appropriately selected taking into consideration the composition of the (meth)acrylic resin composition, the required thickness of the layer of the (meth)acrylic resin composition, etc. The temperature conditions for forming the layer of the (meth)acrylic resin composition are, for example, preferably 180 to 300°C, more preferably 200 to 290°C, and even more preferably 220 to 280°C. The temperature is the temperature of the molten (meth)acrylic resin composition at the die lip of the die (or immediately after extrusion).

[0115] The melt of the resin composition for forming the substrate layer can be extruded from the die in a heated state as necessary. In producing the laminated sheet of this embodiment, the temperature conditions for forming the substrate layer by extrusion molding can be appropriately selected taking into consideration the components of the resin composition as the material, the blending ratio, the required thickness of the substrate layer, and the like. When the substrate layer is formed from a (meth)acrylic resin composition, the temperature conditions for forming the substrate layer are, for example, preferably 180 to 300°C, more preferably 200 to 290°C, and even more preferably 220 to 280°C. The temperature is the temperature of the melt of the resin composition at the die lip of the die (or immediately after extrusion).

[0116] The thickness of the layer of the (meth)acrylic resin composition in the laminate sheet of this embodiment is not particularly limited. The thickness of the layer of the (meth)acrylic resin composition is preferably 0.05 mm or more and 1.0 mm or less, more preferably 0.1 mm or more and 0.5 mm or less, from the viewpoints of antiviral properties, effective suppression of static electricity generation and dust adhesion, recovery of antiviral properties, effective suppression of static electricity generation and dust adhesion by re-bleeding, and transparency. When the laminate sheet contains two or more layers of the (meth)acrylic resin composition, the thicknesses of the two or more layers of the (meth)acrylic resin composition may be the same or different.

[0117] The thickness of the base layer in the laminate sheet of the present embodiment is not particularly limited. For example, from the viewpoint of ensuring the hardness and strength of the laminate sheet, the thickness of the base layer is preferably 0.05 mm or more and 4 mm or less, and more preferably 0.1 mm or more and 3 mm or less.

[0118] <Evaluation method> (1) Haze and its measurement method Haze (Haze 2mmt(%)), which is evaluated as a measure of transparency, can be measured in accordance with JIS K 7136 (corresponding to ISO14782, Plastics-Determination of haze for transparent materials). A specific description will be given below.

[0119] First, haze refers to the percentage of transmitted light that deviates from the incident light by 0.044 rad (2.5°) or more due to forward scattering, among the transmitted light that passes through a test piece that is at least a part of the base material (molded body) of this embodiment.

[0120] In this embodiment, the haze can be measured by any suitable conventionally known device (e.g., Haze Meter HR-100 (manufactured by Murakami Color Research Laboratory)). Examples of devices for measuring the haze include devices equipped with a stable light source, a connecting optical system, an integrating sphere equipped with an aperture, and a photometer. The photometer is preferably composed of a light receiver, a signal processing device, and a display device or recorder.

[0121] Haze measurements are typically performed using multiple cut-out test pieces. The size of the test pieces is not limited, provided that they are large enough to cover the entrance and compensation openings of the integrating sphere.

[0122] First, the test specimen is conditioned for 15 minutes at a temperature of (23±2)°C and a relative humidity of (50±10)% in accordance with ISO291 prior to the measurement of haze.

[0123] Next, the equipment used for the measurement should be placed in an atmosphere maintained at a temperature of (23±2)°C and a relative humidity of (50±10)%, as necessary, and allowed to reach thermal equilibrium for a sufficient period of time before measurement.

[0124] Next, the test piece is placed in the device, and the luminous flux of the incident light transmitted through the test piece is observed, and the haze (%) is calculated according to the following formula (3). Haze = [(τ4 / τ2)-τ3(τ2 / τ1)] × 100 (3)

[0125] In the above formula (3), τ1 represents the luminous flux of the incident light, τ2 represents the total luminous flux transmitted through the test piece, τ3 represents the luminous flux diffused by the device, τ4 represents the light flux diffused by the apparatus and the test piece.

[0126] (2) Surface resistivity and its measurement method The layer of the (meth)acrylic resin composition contained in the sheet and laminate sheet of this embodiment has a surface resistivity (Ω / sq) reduced to at least less than 1.0E+14Ω / sq due to the bleeding of the glycerin fatty acid ester, which is an active ingredient related to antiviral properties, over the entire surface of the surface, and even if the bleeding glycerin fatty acid ester is wiped off multiple times and the surface resistivity increases, the glycerin fatty acid ester bleeds again multiple times each time, thereby reducing the surface resistivity again. As a result, the antiviral properties, as well as the effect of effectively suppressing the generation of static electricity on the surface of the base material and the adhesion of dust, can be maintained for a predetermined period of time.

[0127] In this embodiment, the surface resistivity can be measured in accordance with JIS K 6911 using a resistivity meter (e.g., Hiresta UP MCP-HT-450 model manufactured by Mitsubishi Chemical Analytech Co., Ltd.), which is any suitable measuring device known in the art.

[0128] The surface resistivity can be measured, for example, by conditioning the sample by leaving it for 24 hours under conditions of 23°C and 50% RH, and then measuring it using the device already described in accordance with JIS K 6911. EXAMPLES

[0129] EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to the examples described below.

[0130] The acrylic block copolymers (A-1), (A-2) and rubber particles (A-3) which are component (A) used in the examples and comparative examples described later, as well as the PMMA (content) ratios of the acrylic block copolymers (A-1) and (A-2), and the glass transition temperatures Tg (°C) are as follows: A-1:LA4285 (PMMA ratio: 50%) Tg -45.7℃ A-2: LA2270 (PMMA ratio: 40%) Tg -45℃ A-3: Rubber particles Tg -24.4℃ The acrylic block copolymers (A-1) and (A-2) used were commercially available products (block copolymers having two PMMA blocks bonded to both ends of a PnBA block) manufactured by Kuraray Co., Ltd. The rubber particles (A-3) used in the comparative examples were produced as described in paragraph

[0044] of Japanese Patent No. 54465432.

[0131] The glycerin fatty acid esters (C-1) to (C-2) as component (C) used in the examples and comparative examples described later and their HLB values ​​are as follows. All of the glycerin fatty acid esters used were commercially available products manufactured by Riken Vitamin Co., Ltd. C-1: DL-100 Diglycerol monolaurate HLB value 9.4 C-2: M-300 Glycerin monolaurate HLB value 5.4

[0132] <Example 1> [Preparation of (meth)acrylic resin composition] A (meth)acrylic resin composition was obtained by kneading 75 parts by mass of polymethyl methacrylate (PMMA) (Sumipex LG2, manufactured by Sumitomo Chemical Co., Ltd.), 20 parts by mass of an acrylic block copolymer (LA4285, manufactured by Kuraray Co., Ltd.), and 5 parts by mass of diglycerin monolaurate (DL-100, manufactured by Riken Vitamin Co., Ltd.) using an ME-type Labo Plastomill (manufactured by Toyo Seiki Co., Ltd.) at a rotation speed of 80 rpm for 5 minutes. The composition (mass%) of the (meth)acrylic resin composition is shown in Table 1.

[0133] [Production of molded body (plate)] The (meth)acrylic resin composition obtained as described above was placed in a 2 mm thick frame mold and preheated at 210° C. for 5 minutes. It was then pressed at 2 MPa for 3 minutes, further pressed at 12 MPa for 1 minute, and then cooled at room temperature at 2 MPa for 1 minute to obtain a flat molded product (plate) (thickness 2 mm).

[0134] [Haze Measurement] "Haze (Haze 2mmt(%))" was measured using a haze meter HR-100 (manufactured by Murakami Color Research Laboratory) in accordance with the method of JIS K 7136. The results are shown in Table 1 below.

[0135] [Measurement of surface resistivity] "Surface resistivity (Ω / sq)" was measured in accordance with JIS K 6911 using a resistivity meter (Hiresta UP MCP-HT-450 model, manufactured by Mitsubishi Chemical Analytech Co., Ltd.).

[0136] The plate produced as described above was cut into a sample having a size of 50 mm x 50 mm, and the sample was left for 24 hours under conditions of 23°C and 50% RH. Thereafter, the surface resistivity of the plate was measured.

[0137] The upper limit of the surface resistivity that can be measured by the resistivity meter is 1.0E+14 Ω / sq, and if the surface resistivity exceeds this value, it will be considered to be "OVER."

[0138] [Measurement of surface resistivity immediately after wiping and 3 days after wiping] The surface of the plate prepared as described above was wiped with Bencotton soaked in special grade ethanol (sometimes called the first wipe).

[0139] First, the surface resistivity of the wiped surface of the plate was measured immediately after wiping. Then, the wiped plate was left for 72 hours under conditions of 23°C and 50% RH. After that, the surface resistivity of the wiped surface of the plate was measured.

[0140] [Measurement of surface resistivity immediately after the second wiping and 3 days after wiping] One day after the first wiping and the measurement of surface resistivity three days after wiping, a second wiping was performed in the same manner as the first wiping already described, and the surface resistivity was also measured immediately after wiping and three days after wiping in the same manner.

[0141] <Examples 2 to 9> Except for the compositions shown in Table 1 below, (meth)acrylic resin compositions according to Examples 2 to 9 were prepared in the same manner as in Example 1 above, and the haze and surface resistivity were measured in the same manner as in Example 1 above. The results are shown in Table 1 below.

[0142] <Comparative Examples 1 to 4> Except for the compositions shown in Table 2 below, (meth)acrylic resin compositions according to Comparative Examples 1 to 4 were prepared in the same manner as in Example 1 above, and the haze and surface resistivity were measured in the same manner as in Example 1 above. The results are shown in Table 2 below.

[0143] [Table 1]

[0144] [Table 2]

[0145] According to Examples 1 to 9 which satisfy the requirements of the present invention, the surface resistivity can be reduced, and as a result, the glycerin fatty acid ester bleeds onto the surface of the molded article, which shows that the molded article has antiviral properties, and furthermore, can suppress the generation of static electricity and the adhesion of dust due to the generation of static electricity.

[0146] Furthermore, according to Examples 1 to 9 which satisfy the requirements of the present invention, even if the glycerin fatty acid ester is repeatedly wiped off from the surface of the molded article by alcohol disinfection treatment, the glycerin fatty acid ester re-bleeds onto the surface at least within 3 days after wiping off, thereby restoring the antiviral properties, as well as the effect of suppressing the generation of static electricity and the adhesion of dust due to the generation of static electricity.

[0147] Furthermore, according to Examples 1 to 6 which satisfy the requirements of the present invention, the transparency can be further improved, and the film can be suitably applied to applications requiring transparency, and as a result, the film can be applied to a wider range of applications.

[0148] On the other hand, according to Comparative Examples 1 to 4 which do not satisfy at least one of the requirements of the present invention, it was shown that the reduction in surface resistivity (imparting of antiviral properties) and / or recovery of the reduction in surface resistivity (recovery of antiviral properties) by multiple re-bleeding in one or more repeated wipings could not be achieved.

Claims

1. A (meth)acrylic resin composition comprising a (meth)acrylic resin, at least one soft material having a glass transition temperature (Tg) of −30° C. or lower, and a glycerin fatty acid ester, in the (meth)acrylic resin composition, when the total content of the (meth)acrylic resin, the soft material having at least one glass transition temperature (Tg) of −30° C. or lower, and the glycerin fatty acid ester is taken as 100 mass%, the content of the (meth)acrylic resin is in the range of 35 mass% or more and 84 mass% or less, The content of the soft material having at least one glass transition temperature (Tg) of −30° C. or lower is in the range of 15% by mass or more and 60% by mass or less, A (meth)acrylic resin composition having a glycerin fatty acid ester content of 1% by mass or more and 15% by mass or less.

2. 2. The (meth)acrylic resin composition according to claim 1, wherein the soft material having at least one glass transition temperature (Tg) of −30° C. or lower is an acrylic soft material.

3. The (meth)acrylic resin composition according to claim 2 , wherein the acrylic soft material is an acrylic block copolymer.

4. The acrylic block copolymer is a methacrylate polymer block; Acrylate polymer block and The (meth)acrylic resin composition according to claim 3 , which is a block copolymer comprising:

5. The acrylic block copolymer is The content of the methacrylic acid ester polymer block is in the range of 30% by mass or more and 60% by mass or less, The (meth)acrylic resin composition according to claim 4, which is a block copolymer having an acrylic acid ester polymer block content in the range of 40% by mass or more and 70% by mass or less.

6. The (meth)acrylic resin composition according to claim 1 , wherein the glycerin fatty acid ester has an HLB value in the range of 5 or more and 12 or less.

7. The (meth)acrylic resin composition according to claim 6 , wherein the glycerin fatty acid ester is a glycerin saturated fatty acid ester.

8. A formed material obtained by molding the (meth)acrylic resin composition according to any one of claims 1 to 7.

9. The base material according to claim 8, which is a sheet formed from the (meth)acrylic resin composition.

10. A laminated sheet comprising one or more layers of the sheet according to claim 9.

11. The laminate sheet according to claim 10, further comprising a base layer, and layers of the (meth)acrylic resin composition are provided on both a first main surface and a second main surface facing each other in a thickness direction of the base layer so as to sandwich the base layer.

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