WO2023145390A1 - (meth)acrylic resin composition - Google Patents

Abstract

A (meth)acrylic resin composition having antiviral properties and antistatic properties. The (meth)acrylic resin composition comprises a (meth)acrylic resin, a flexible material having at least one glass transition temperature (Tg) of -30°C or lower, and a glycerin fatty acid ester, wherein when the total content of the (meth)acrylic resin, the flexible 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%, then the content of the (meth)acrylic resin is in the range of 35-84 mass%, the content of the flexible material having at least one glass transition temperature (Tg) of -30°C or lower is in the range of 15-60 mass%, and the content of the glycerin fatty acid ester is in the range of 1-15 mass%.

Description

(Meth)acrylic resin composition

The present invention relates to a (meth)acrylic resin composition, a sheet formed from the (meth)acrylic resin composition, and a laminate containing the sheet.

To provide a sheet-shaped molded article having excellent surface smoothness, moldability, flexibility, and high light transmittance for short-wavelength light, and a thermoplastic polymer composition for forming the sheet-shaped molded article. A thermoplastic polymer composition containing the desired acrylic block copolymer and an acrylic resin is known (see Patent Document 1).

Further, for the purpose of improving the antistatic property of the (meth)acrylic resin composition, there is known an aspect in which a glycerin monofatty acid ester is added to the (meth)acrylic resin composition (see Patent Document 2). .

WO2010/055798 JP-A-5-239305

Due to the recent spread of new coronavirus infections, it is desired to impart antiviral properties to devices and instruments that may come into contact with the human body, and molded products made from (meth)acrylic resin compositions are expected to come into contact with the human body. The same applies to devices, instruments, etc. included as members in a manner to do so, for example.

However, in the (meth)acrylic resin compositions and molded articles thereof according to Patent Documents 1 and 2, for example, no consideration is given to imparting antiviral properties to the new coronavirus, and even if antiviral properties are provided, Even if it can be demonstrated, for example, from the viewpoint of preventing infection with the new coronavirus, the surface treatment with ethanol (alcohol disinfection treatment), which is recommended for processing equipment and instruments, etc. In some cases, the properties are lost, and the antistatic property is lost.

The inventors of the present invention conducted intensive studies to solve the above problems, and found that a (meth)acrylic resin, a soft material having at least one glass transition temperature (Tg) of −30° C. or less, and a glycerin fatty acid ester were found. The inventors have found that the above problems can be solved by using a (meth)acrylic resin composition containing a certain amount, and have completed the present invention.

That is, the present invention provides the following [1] to [11].
[1] 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 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 less, and the glycerin fatty acid ester is 100% by mass , the (meth)acrylic resin content is in the range of 35% by mass or more and 84% by 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] 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;
The (meth)acrylic resin composition according to [3], which is a block copolymer containing an acrylic acid ester polymer block.
[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 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 shaped material obtained by molding the (meth)acrylic resin composition according to any one of [1] to [7].
[9] The formed material according to [8], which is a sheet obtained by molding the (meth)acrylic resin composition.
[10] A laminated sheet comprising one or more layers of the sheet according to [9].
[11] Further comprising a substrate layer, the layer of the (meth)acrylic resin composition is provided on both the first main surface and the second main surface facing each other in the thickness direction of the substrate layer. The laminated sheet according to [10], which is provided so as to sandwich the material layer.

According to the present invention, it is possible to maintain antiviral properties against the new coronavirus, for example, in a molded material (molded article) obtained by molding a (meth)acrylic resin composition, even by surface treatment with ethanol multiple times. Furthermore, it is possible to provide a (meth)acrylic resin composition that can suppress the generation of static electricity and the adhesion of dust due to the generation of static electricity.

Hereinafter, embodiments of the present invention will be specifically described. In addition, the present invention is not limited by the following description. The embodiments described below can be modified as appropriate without departing from the gist of the present invention.

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

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

<(Meth) acrylic resin>
Examples of (meth)acrylic resins 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, or two types of Examples include copolymers of the above monomers, copolymers of (meth)acrylic monomers and other monomers, and the like.

In this specification, the term "(meth)acryl" means "acryl" or "methacryl".

As the (meth)acrylic resin, it is preferable to use a methacrylic resin because it has excellent hardness, weather resistance, and transparency. A methacrylic resin is a polymer obtained by polymerizing a monomer mainly composed of a methacrylate (alkyl methacrylate).

(Meth)acrylic resins include, for example, a homopolymer (polyalkyl methacrylate) of methacrylic acid ester as a monomer, a copolymer of methacrylic acid ester, and 50% by mass or more of methacrylic acid ester and 50% by mass or less. and copolymers with monomers other than methacrylic acid esters.

When the (meth)acrylic resin is a copolymer of a methacrylic acid ester and a monomer other than the methacrylic acid ester, the methacrylic acid ester is 70% by mass or more with respect to 100% by mass of the total amount of the monomers. Preferably, the monomer other than the methacrylic acid ester is 30% by mass or less, the methacrylic acid ester is 90% by mass or more, and the monomer other than the methacrylic acid ester is 10% by mass or less. is more preferable.

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.

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; ; N-substituted maleimides such as phenylmaleimide, cyclohexylmaleimide and methylmaleimide. 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 from the viewpoint of improving heat resistance.

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

In the above formula (1), R ₁ represents a hydrogen atom or a methyl group, and when R 1 is a hydrogen atom, R ₂ represents an alkyl group _having 1 to 8 carbon atoms, and R ₁ is a methyl group. In some cases R ₂ represents an alkyl group of 2 to 8 carbon atoms.

In the condition (a2), the total amount of the structural unit derived from methyl methacrylate and at least one structural unit derived from the (meth)acrylic acid ester represented by the formula (1) is 100% by mass. Preferably.

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

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

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 according to a method in accordance with JIS K 7210, which is usually 0.1 to 30 g/10 minutes, (Meth) From the viewpoint of improving the strength of the molded product, which is a molded product obtained by molding the acrylic resin composition, and improving the moldability, it is preferably 0.2 to 20 g / 10 minutes, more preferably 0 .5 to 15 g/10 minutes.

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

In the present embodiment, the (meth)acrylic resin is JIS from the viewpoint of improving heat resistance.
The Vicat softening temperature (VST) measured according to the method according to K7206 is preferably 90°C or higher, more preferably 100°C or higher, and even more preferably 102°C or higher. The VST of the (meth)acrylic resin can be appropriately set by adjusting the types and ratios of the monomers and the molecular weight of the (meth)acrylic resin.

The (meth)acrylic resin can be prepared (synthesized) by polymerizing the monomers already described by any suitable conventionally known method such as suspension polymerization or bulk polymerization. In the preparation, properties such as MFR, Mw, and VST of the (meth)acrylic resin can be adjusted within preferred ranges by further adding, for example, a conventionally known suitable chain transfer agent. The amount of the chain transfer agent to be added can be appropriately determined according to the type and ratio of the selected monomers and the required properties.

<Soft material having at least one glass transition temperature (Tg) of −30° C. or lower>
The (meth)acrylic resin composition of the present embodiment contains “a soft material having at least one glass transition temperature (Tg) of −30° C. or lower. A material that can be deformed by pressure at

In the present embodiment, the glass transition temperature of the “soft material having at least one glass transition temperature (Tg) of −30° C. or less” is preferably −30° C. or less, more preferably −35° C. or less. The temperature is preferably −40° C. or higher, and more preferably −40° C. or higher.

In this embodiment, the "glass transition temperature (Tg)" can be measured according to JIS-K7121, for example. Specifically, the glass transition temperature (Tg) can be measured according to the measuring method described in paragraph [0061] of JP-A-2003-342388.

The glass transition temperature can be measured using any conventionally known suitable measuring instrument (for example, "DSC7020" manufactured by Hitachi High-Tech Science Co., Ltd., which is a differential scanning calorimeter).

Specifically, the soft material can be completely melted under an inert gas atmosphere, and then measured based on the DSC curve obtained from a given temperature profile.

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 the present embodiment include polybutadiene and styrene-ethene-butene-styrene. block polymers, PEO-based block polymers, PLA-based block polymers, polyethylene oxide-polypropylene oxide block polymers (PEO-PPO block polymers), acrylic soft materials, and the like. Also, with respect to the soft material described above, it is more preferable that one of the block components has a high affinity for PMMA. Examples include acrylic soft materials, PEO block polymers, PLA block polymers, and the like.

As 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 the present embodiment, for example, the active ingredient glycerin fatty acid ester is added several times. From the viewpoint of rebleeding effectively over the , it is more preferable to use an acrylic soft material.

In the present embodiment, it is preferable to use an acrylic block copolymer as the acrylic soft material from the viewpoint of the already-explained effect of rebleeding of the glycerin fatty acid ester multiple times and from the viewpoint of availability. The acrylic block copolymer contains a block component A and a block component B. The block component A has a high affinity with PMMA (for example, PLA, PEO, PVDF, SMA, PMMA, etc.), and the block component B has A low Tg is preferred.

Here, acrylic block copolymers that can be suitably applied to the (meth)acrylic resin composition of the present embodiment will be described.

In the present embodiment, the acrylic block copolymer includes 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. It is a block copolymer. The acrylic block copolymer may contain only one methacrylic acid ester polymer block (b1), or may contain two or more. In addition, the acrylic block copolymer (B) may contain only one acrylic acid ester polymer block (b2), or may contain two or more.

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.

As a bonding aspect of the acrylic block copolymer, for example, an aspect 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), i.e., the formula: ( A diblock copolymer having a structure represented by b1)-(b2); an aspect in which one end of an acrylic ester polymer block (b2) is bonded to each of both ends of a methacrylic ester polymer block (b1) , that is, a triblock copolymer represented by the formula: (b2)-(b1)-(b2), a methacrylic ester polymer block (b1) at each of both ends of the acrylic ester polymer block (b2) A triblock copolymer having a structure represented by the formula: (b1)-(b2)-(b1) is exemplified.

In addition, as a form of bonding in the acrylic block copolymer, a block copolymer ([(b1) -(b2)-] structure represented by nX (n represents an integer of 2 or more, X represents the residue of the coupling agent used, and the same applies hereinafter)); A block copolymer (structure represented by [(b2)-(b1)-]nX) in which the structures represented by -(b1)" are bonded to form a radial configuration; a plurality of "(b1)-( A block copolymer (structure represented by [(b1)-(b2)-(b1)-]nX) in which the structures represented by b2)-(b1)” are bonded to form a radial configuration; A block copolymer in which the structures represented by “(b2)-(b1)-(b2)” are bonded and configured radially (represented by [(b2)-(b1)-(b2)-] nX and a block copolymer having a branched structure.

In the present embodiment, the acrylic block copolymer is preferably the already described diblock copolymer, triblock copolymer, or star block copolymer, represented by the formula: (b1)-(b2). A diblock copolymer having a structure, a formula: a triblock copolymer having a structure represented by (b1)-(b2)-(b1), a formula: [(b1)-(b2)-]nX A star-shaped block copolymer having a structure represented by (b1)-(b2)-(b1)-]nX is more preferable, and an acrylic ester polymer block ( An acrylic block copolymer having a structure in which one methacrylic acid ester polymer block (b1) is bonded to each end of b2), i.e., a structure represented by the formula: (b1)-(b2)-(b1) More preferably, polymers are used.

In the present embodiment, the acrylic block copolymer is a (meth)acrylic resin composition, and further, from the viewpoint of ensuring good transparency in the molded material, the acrylic block copolymer is a methacrylic acid ester polymer. A block copolymer having a block content of 30% by mass or more and 60% by mass or less and an acrylic acid ester polymer block content of 40% by mass or more and 70% by mass or less is preferable.

In the acrylic block copolymer, the methacrylic acid ester copolymer block (b1) is a copolymer block whose main structural unit is a structural unit derived from a methacrylic acid ester. The proportion of structural units derived from 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, and still more preferably 95% by mass or more. , particularly preferably 98% by mass or more.

Examples of the methacrylic acid ester, which is a monomer that can constitute the methacrylic acid ester copolymer block of the present embodiment, include methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-methacrylate, butyl, isobutyl methacrylate, sec-butyl methacrylate, tert-butyl methacrylate, amyl methacrylate, isoamyl methacrylate, n-hexyl methacrylate, cyclohexyl methacrylate, 2-ethylhexyl methacrylate, pentadecyl methacrylate, dodecyl methacrylate, Mention may be made of 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 heat resistance, methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, tert-butyl methacrylate, cyclohexyl methacrylate, isobornyl methacrylate, etc. Methacrylic acid alkyl esters 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.

The methacrylic acid ester polymer block (b1) may contain structural units derived from monomers other than the methacrylic acid ester as long as the object and effect of the present invention are not impaired. The ratio of structural units derived from monomers other than 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, and still more preferably 5% by mass. % or less, particularly preferably 2 mass % or less.

Examples of monomers other than methacrylic acid esters that can constitute the methacrylic acid ester copolymer block of the present embodiment include acrylic acid esters, unsaturated carboxylic acids, aromatic vinyl compounds, olefins, conjugated dienes, acrylonitrile, methacrylic acid esters, ronitrile, 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 these monomers other than the methacrylic acid ester singly or in combination of two or more thereof with the above-described methacrylic acid ester.

The methacrylic acid ester polymer block (b1) is composed of a polymer having a refractive index in the range of 1.485 to 1.495. It is preferable from the viewpoint of improving the property.

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, still more preferably 12,000 or more and 100,000 or less. be.

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

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 further It is preferably 20,000 or more and 100,000 or less. Here, when only one methacrylic acid ester polymer block (b1) is included in the acrylic block copolymer, the weight average molecular weight of the methacrylic acid ester polymer block (b1) is Mw (b1). Further, when two or more methacrylic acid ester polymer blocks (b1) are included in the acrylic block copolymer, and the two or more methacrylic acid ester polymer blocks (b1) have the same weight average molecular weight. has such a weight average molecular weight as Mw(b1).

The content (percentage) of the methacrylic acid ester polymer block (b1) in the acrylic block copolymer is preferably 10% by mass or more from the viewpoint of improving transparency, flexibility, workability, and surface smoothness. % by mass or less, more preferably 20% by mass or more and 55% by mass or less. If the ratio of the methacrylic acid ester polymer block (b1) in the acrylic block copolymer is within the above range, the transparency, flexibility, bending resistance, and durability of the (meth)acrylic resin composition and the cast material can be improved. Properties such as impact resistance and flexibility can be improved. When the acrylic block copolymer contains two or more methacrylic acid ester polymer blocks (b1), the above ratio is calculated based on the total mass of all methacrylic acid ester polymer blocks (b1). Just do it.

The acrylate polymer block (b2) is a block copolymer whose main structural unit is a structural unit derived from an acrylate monomer. The proportion of structural units derived from 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, and still more preferably 60% by mass or more. , particularly preferably 90% by mass or more.

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

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

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, vinylketone, chloride vinyl, vinylidene chloride, vinylidene fluoride and the like. The acrylic acid ester polymer block (b2) can be formed by copolymerizing one or a combination of two or more of these monomers other than the acrylic acid ester with the acrylic acid ester monomer.

As long as the objects and effects of the present invention are not impaired, the acrylic block copolymer can be used as a polymer block separate from the methacrylic acid ester polymer block (b1) and the acrylic acid ester copolymer block (b2), It may further contain other polymer blocks (b3) derived from monomers other than acrylate and methacrylate. The form of bonding 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. The mode of bonding between the other polymer block (b3) and the methacrylic acid ester polymer block (b1) and the acrylic acid ester polymer block (b2) is, for example, the formula: (b1)-((b2)-( b1)) n-(b3), and represented by the formula: (b3)-(b1)-((b2)-(b1) n-(b3) (where n represents an integer of 1 to 20) The aspect to be carried out is mentioned.

Other monomers that can constitute the polymer block (b3) include 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, m-methylstyrene; vinyl acetate, vinylpyridine, acrylonitrile, methacrylonitrile, vinyl ketone, vinyl chloride, vinylidene chloride, vinylidene fluoride, acrylamide, Methacrylamide, ε-caprolactone, and valerolactone.

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 an acrylic block copolymer include a method of living polymerization of monomers capable of constituting various polymer blocks already described (living polymerization method). Examples of such a living polymerization method include a method of anionic polymerization in the presence of a mineral acid salt such as an alkali metal or alkaline earth metal salt using an organic alkali metal compound as a polymerization initiator, and a method of polymerizing an organic alkali metal compound. A method of anionic polymerization in the presence of an organic aluminum compound using an initiator, a method of polymerizing using an organic rare earth metal complex as a polymerization initiator, a method of polymerizing using an α-halogenated ester compound as an initiator, and radical polymerization in the presence of a copper compound. A method of polymerization can be mentioned. Another example is a method of producing a mixture containing an acrylic block copolymer by polymerizing components that can constitute each block using a polyvalent radical polymerization initiator or a polyvalent radical chain transfer agent. Among these methods for producing acrylic block copolymers, organic It is preferable to adopt a method of anionic polymerization in the presence of an organoaluminum compound using an alkali metal compound as a polymerization initiator.

In this embodiment, a commercially available product can also be used as the acrylic block copolymer. 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), LA2270 (manufactured by Kuraray Co., Ltd. ) manufactured by Kuraray Co., Ltd., PMMA ratio: 40%, Tg: -45°C).

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

In the present embodiment, the glycerin fatty acid ester has a function of exhibiting antiviral properties particularly against the novel coronavirus, and furthermore, by exuding (bleeding) on the surface of the molded body and covering the surface, It has the function of suppressing the generation of static electricity and the adhesion of dust.

In this embodiment, the glycerin fatty acid ester is a glycerin fatty acid ester having an HLB value in the range of 5 or more and 12 or less. The HLB value bleeds the glycerin fatty acid ester to the surface, and even if it is wiped off multiple times, the glycerin fatty acid ester bleeds again each time. is preferably 5.4 or more, and more preferably 9.4 or less, from the viewpoint of recovery of effective suppression of . The HLB value is preferably in the range of 5 or more and 9.4 or less, or in the range of 5.4 or more and 12 or less, and more preferably in the range of 5.4 or more and 9.4 or less.

Here, the HLB (Hydrophilic Lipophilic Balance) value is a parameter that can take values from 0 to 20, and the closer to 0, the higher the lipophilicity (hydrophobicity), and the closer to 20, the higher the hydrophilicity. is a parameter that represents A compound such as paraffin having only a hydrophobic group without a hydrophilic group has an HLB value of 0, and a compound having only a hydrophilic group without a hydrophobic group such as polyethylene glycol has an HLB value. is 20, and compounds having both hydrophilic and hydrophobic groups in one molecule will have a value between 1 and 20. Therefore, the greater the hydrophilicity of the hydrophilic group relative to the hydrophobicity of the hydrophobic group in the molecule, the higher the HLB value and the higher the water solubility. Therefore, the smaller the hydrophilicity of the hydrophilic group, the smaller the HLB value and the lower the water solubility.

The HLB value of a given compound (molecule) can be calculated, for example, by Griffin's method using the following formula (2).

HLB value = 20 × sum of chemical formula weights of hydrophilic moieties/sum of chemical formula weights of hydrophobic moieties (2)

In the present 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. Moreover, as fatty acid ester which comprises a glycerin fatty acid ester, a mono-fatty-acid ester, a di-fatty-acid ester, and a tri-fatty-acid ester are mentioned, for example. Among these, the fatty acid ester is preferably mono-fatty acid ester or di-fatty acid ester.

Examples of glycerin that can constitute glycerin fatty acid esters that can be used in the present embodiment include monoglycerin, diglycerin, triglycerin, tetraglycerin, pentaglycerin, and decaglycerin. Among these, glycerin that can constitute a glycerin fatty acid ester is preferably monoglycerin, diglycerin, or decaglycerin, and more preferably diglycerin.

Specific examples of glycerin fatty acid esters include monoglycerin monocaprylate (HLB value 7.0), monoglycerin monocaprate (HLB value 6.8), monoglycerin monolaurate (HLB value 5.0). 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, tetraglycerin monomyristate, pentaglycerin monocaprylate, pentaglycerin monocaprate , pentaglycerin monolaurate, pentaglycerin monomyristate, decaglycerin monooleate (decaglycerin oleate) (HLB value 12), among these, monoglycerin monocaprate (HLB value 6.8), Glycerin saturated fatty acid esters such as monoglycerin monolaurate (HLB value 5.4) and diglycerin monolaurate (HLB value 9.4) are preferable. .4) is more preferably used.

It should be noted that the HLB value of the glycerin fatty acid ester can be applied with reference to, for example, the values disclosed in conventionally known literature. Moreover, as a glycerin fatty acid ester, you may obtain and use a commercial product, for example.

<(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 the already described (meth) acrylic resin, the glass transition temperature (Tg ) and the total content of the glycerin fatty acid ester is 100% by mass, it is usually more than 20% by mass and less than 85% by mass, and maintains antiviral properties and generates static electricity. Furthermore, from the viewpoint of effectively suppressing adhesion of dust, it is preferably 42% by mass or more, more preferably 45% by mass or more, further preferably 47.5% by mass or more, and 55% by mass. % or less, more preferably 70% by mass or less, preferably 42% by mass or more and 84% by mass or less, more preferably 35% by mass or more and 84% by mass or less. It is 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.

(2) A soft material having at least one glass transition temperature (Tg) of −30° C. or lower The (meth)acrylic resin composition of the present embodiment has at least one glass transition temperature (Tg) of −30° C. or lower. The content of the soft material is 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, when the total content is 100% by mass. In addition, it is usually more than 10% by mass and less than 75% by mass, and from the viewpoint of maintaining antiviral properties, static electricity generation, effective suppression of dust adhesion, and particularly good transparency, 15% by mass % or more and 60% by mass or less, preferably 25% by mass or more, preferably 50% by mass or less, more preferably 40% by mass or less, and particularly improving transparency. From the viewpoint, the range is preferably 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.

(3) Glycerin fatty acid ester In the (meth)acrylic resin composition of the present embodiment, the content of the glycerin fatty acid ester is the already described (meth)acrylic resin, and the glass transition temperature (Tg) of -30 ° C. or less is at least 1 When the total content of the soft material and glycerin fatty acid ester is 100% by mass, it is usually more than 0.5% by mass and less than 15% by mass, maintains antiviral properties, generates static electricity, and 1.0% by mass or more and 15% by mass or less from the viewpoint of effective suppression of dust adhesion, especially antiviral properties due to repeated rebleeding, generation of static electricity, and restoration of effective suppression of dust adhesion. , preferably 2.5% by mass or more, preferably 8% by mass or less, more preferably 5% by mass or less, from the viewpoint of maintaining effective antiviral properties. 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 cast material, 1.0% by mass More than 10% or less is preferable.

In the (meth)acrylic resin composition of the present embodiment, the (meth)acrylic resin, a soft material having at least one glass transition temperature (Tg) of −30° C. or less, and a glycerin fatty acid ester are blended in the above proportions. , antiviral properties, and can effectively suppress the generation of static electricity and dust adhesion on the surface of the shaped material, and in particular, the glycerin fatty acid ester that imparts antiviral properties is bled to the surface, and further, for example, ethanol Even if the glycerin fatty acid ester bleeding onto the surface of the material is wiped off several times by the alcohol disinfection treatment using , The glycerin fatty acid ester can be repeatedly rebleed each time it is wiped off its surface, and has antiviral properties, and also effectively suppresses the generation of static electricity and the adhesion of dust. transparency can be imparted and these properties can be maintained over a period of time.

The amount of other resins that can be contained in the (meth)acrylic resin composition of the present embodiment is preferably 20% by mass or less with respect to the total amount (100% by mass) of the (meth)acrylic resin composition, It is more preferably 10% by mass or less, and even more preferably 5% by mass or less.

Other resins that may be contained in the (meth)acrylic resin composition of the present embodiment include, for example, polycarbonate resins, polyamide resins, acrylonitrile-styrene copolymers, methyl methacrylate-styrene copolymers, and polyethylene terephthalate. .

(4) Other components The (meth)acrylic resin composition of the present embodiment contains other components commonly used in (meth)acrylic resin compositions, provided that the effects of the present invention are not impaired. It may contain further.

Other components that the (meth)acrylic resin composition of the present embodiment may contain include, for example, crosslinked rubber particles, ultraviolet absorbers, slip agents, antioxidants, release agents, and antistatic agents.

The crosslinked rubber particles that are other components, for example, have at least a core portion and a coating layer that covers the core portion, and at least one of the core portion and the coating layer has a carbon-carbon unsaturated bond. A multi-layered rubber particle formed from a material having two or more structural units derived from a polyfunctional monomer may be mentioned.

Examples of UV absorbers that are other components include benzophenone UV absorbers, cyanoacrylate UV absorbers, benzotriazole UV absorbers, malonic acid ester UV absorbers, and oxalanilide UV absorbers. be done.

Examples of slip agents, which are other components, include silicone oil and polysiloxane compounds.

　Antioxidants that are other components include, for example, phenolic antioxidants, sulfur-based antioxidants, and phosphorus-based antioxidants.

Other components of the mold release agent include, for example, higher fatty acid esters, higher fatty alcohols, higher fatty acids, higher fatty acid amides, higher fatty acid metal salts, and fatty acid derivatives different from the "glycerin fatty acid ester" already described. .

Examples of antistatic agents that are other components include conductive inorganic particles, tertiary amines, quaternary ammonium salts, cationic acrylic acid ester derivatives, and cationic vinyl ether derivatives.

<Method for producing (meth)acrylic resin composition>
The (meth)acrylic resin composition of the present embodiment includes the already described (meth)acrylic resin, a soft material having at least one glass transition temperature (Tg) of −30° C. or less, a glycerin fatty acid ester, and the desired Other components can be manufactured (prepared) by carrying out a kneading step using any suitable conventionally known equipment and conditions.

In the present embodiment, the temperature conditions in the (melting) kneading process are not particularly limited. The temperature conditions can be arbitrary and suitable conditions in consideration of the selected components, their amounts, properties, and the like. In the melt-kneading step, for example, the temperature from the raw material inlet to the outlet of the extruder may be 180°C to 260°C.

As equipment that can be used in the kneading process, conventionally known and suitable mixers and kneaders can be used. Specific examples of such devices include single-screw kneaders, twin-screw kneaders, multi-screw extruders, Henschel mixers, Banbury mixers, kneaders, and roll mills. Moreover, when it is necessary to increase the rotational speed in the kneading step, for example, a high shear processing device may be used.

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

According to the cast material of the present embodiment, the glycerin fatty acid ester already described bleeds on the surface, and the glycerin fatty acid ester exhibits antiviral properties as an active ingredient, and furthermore, static electricity on the surface of the cast material It is possible to effectively suppress the occurrence of dust and the adhesion of dust, and even if the glycerin fatty acid ester is wiped off, by rebleeding the glycerin fatty acid ester multiple times, antiviral and static electricity It can be used as a shaped material capable of recovering (maintaining) the effect of suppressing dust generation and dust adhesion over multiple times.

Here, forged materials refer to parts, members, and final products themselves that are given a predetermined shape by applying predetermined heat and force to materials such as resin compositions, rubber, glass, and metals. Say. That is, the molded material having antiviral properties of the present embodiment is a molded article formed into a predetermined shape by molding the (meth)acrylic resin composition described above.

In the present embodiment, the shape, thickness, and other sizes of the cast material that can be manufactured are not particularly limited. In the present embodiment, the preform is preferably a sheet (layered body, plate-shaped body) obtained by molding the (meth)acrylic resin composition described above.

In addition, in the present embodiment, it is also possible to form a laminated sheet including one or more sheets obtained by molding the (meth)acrylic resin composition described above as a layer of the (meth)acrylic resin composition. That is, the cast material of the present embodiment includes a laminated sheet (laminate) including a layer containing the (meth)acrylic resin composition described above.

The cast material obtained by molding the (meth)acrylic resin composition of the present embodiment has antiviral properties, particularly against the new coronavirus, and effectively suppresses the generation of static electricity on the surface of the cast material and thus the adhesion of dust. can be done. Therefore, it can be suitably used as a device, instrument, etc. that can come into contact with the human body, or as a material included in the device, instrument, or the like.

Since the molded material obtained by molding the (meth)acrylic resin composition of the present embodiment has the properties as already described, it can be used, for example, when transparency is not required in applications such as handrails, door handles, containers, It can be suitably applied to members such as container lids and wall materials, which inevitably come into contact with the human body at many occasions when used.

In addition, if transparency is required for the application, it can be installed on a desk to separate customers who are adjacent or face each other at a store, etc., or between attendees who are adjacent or face each other at a meeting, etc. ) Screens, partitions, cover members for covering product samples in vending machines, cover members for lamps, display panel members such as protective sheets located on the top surface of touch sensor panels, automobiles, motorcycles It can be suitably used as a member for a meter panel for vehicles such as.

(1) Sheet The thickness of the sheet, which is the material formed by molding the (meth)acrylic resin composition of the present embodiment, may be appropriately selected according to the application, and is not particularly limited. In this embodiment, the thickness of the sheet is preferably 100 to 4000 μm, more preferably 200 to 3000 μm, when applied to screens and partitions, for example.

(2) Laminated sheet In the present embodiment, the laminated sheet includes one or more sheets obtained by molding the (meth)acrylic resin composition described above as a layer of the (meth)acrylic resin composition. The layer of the (meth)acrylic resin composition is preferably provided so as to cover at least the surface expected to come into contact with the human body.

In the present embodiment, the laminated sheet further includes a substrate layer from the viewpoint of improving hardness and strength, and the layer of the (meth)acrylic resin composition faces the thickness direction of the substrate layer. It is preferable to have a configuration in which the substrate layers are provided on both sides of the first main surface and the second main surface so as to sandwich the base material layer. The substrate layer may include not only one layer but also two or more layers.

Here, the thickness of the base material layer can be any suitable thickness in consideration of the use of the laminated sheet. When the laminated sheet is applied to, for example, a screen or a partition, the thickness of the base layer is preferably 500-4000 μm, more preferably 1000-3000 μm, from the viewpoint of shape retention.

The material for the base material layer is not particularly limited and may be selected from conventionally known and suitable materials according to the application of the laminated sheet. Examples of the material of the base material layer include (meth)acrylic resin, styrene resin, MS resin, polycarbonate resin and the like. Especially when transparency is required for the application, the transparency of the entire laminated sheet can be increased by combining with a highly transparent substrate layer. Therefore, a transparent material is used as the material for the substrate layer. is preferred.

In addition, when the laminated sheet is, for example, a screen or partition that is assumed to be used face-to-face, and is particularly required to have transparency (visible light transmittance), the material of the base layer is the material of the present embodiment. It is preferably a (meth)acrylic resin composition that may have a different composition and blending ratio from the (meth)acrylic resin composition. Here, from the viewpoint of ensuring transparency, the material of the substrate layer is preferably composed only of (meth)acrylic resin, and the (meth)acrylic resin composition further includes other resins such as vinylidene fluoride resin. It can be a thing.

<Manufacturing method of raw materials>
The method for manufacturing the cast material of the present embodiment is not particularly limited. Examples of the method for producing the cast material of the present embodiment include a method of molding the already-described (meth)acrylic resin composition using a conventionally known arbitrary suitable molding machine.

Extrusion molding and injection molding are examples of methods for manufacturing the cast material of the present embodiment. In the case of making the cast material into a more complicated shape, for example, an injection molding machine is used as the molding machine, and the (meth)acrylic resin composition is injected into the mold of the molding machine and molded. A molding method may be used.

When forming a sheet or laminated sheet as already described, it is preferable to use an extrusion molding method. In particular, when producing a laminated sheet in which the material of the substrate layer is a resin composition to which an extrusion molding method can be applied, typified by a (meth)acrylic resin composition, the substrate layer and the (meth)acrylic of the present embodiment A layer of a (meth)acrylic resin composition containing a resin composition can be molded at the same time, and a laminated sheet can be integrally produced more easily.

Below, the manufacturing method of the cast material of the present embodiment will be described by taking the manufacturing method by the extrusion molding method as an example.

The manufacturing method of the cast material of the present embodiment includes a step of preparing a (meth)acrylic resin composition and a step of extruding the prepared (meth)acrylic resin composition into a cast material. Each step will be specifically described below.

(1) Step of preparing a (meth)acrylic resin composition This step is a step of preparing a (meth)acrylic resin composition to be supplied to an extruder.

In the present embodiment, the properties of the methacrylic resin composition supplied to the extruder are not particularly limited. The shape, size, and the like of the (meth)acrylic resin composition to be supplied to the extruder may be set within an arbitrary and suitable range in consideration of the extruder to be used, applicable conditions, and the like.

(2) A step of extruding a (meth)acrylic resin composition into a cast material. be.

Specifically, the sheet, which is an example of the cast material of the present embodiment, is manufactured by extruding a molten (meth)acrylic resin composition from a die of an extruder and molding it with a die lip according to a conventional method. can do.

A laminated sheet that is an example of the formed material of the present embodiment, for example, the sheet as a layer of a (meth)acrylic resin composition, the first main surface facing the thickness direction of the base material layer and Laminated sheets having a two-kind three-layer structure (layer of (meth)acrylic resin composition/base layer/(meth)acrylic resin) provided on both sides of the second main surface so as to sandwich the base layer A laminated sheet in which layers of the composition are laminated in order) can be produced, for example, as follows.

First, a melt of the (meth)acrylic resin composition of the present embodiment already described and a melt of the resin composition that is the material of the base layer are prepared.

Next, for example, using an extruder equipped with a multi-manifold die, the melted resin composition that is the material of the base layer is extruded from the middle die lip, and at the same time, the upper die lip and the lower die lip are melted. The (meth)acrylic resin composition of the present embodiment is extruded, and the extruded molded body is, if necessary, cooled using a conventionally known arbitrary suitable cooling roll, or other rolls such as a conveying roll The (meth)acrylic of the present embodiment is sandwiched between the first main surface and the second main surface of the base material layer molded in the middle stage, such as by further molding using A laminated sheet, which is a laminate having a two-kind three-layer structure, including a (meth)acrylic resin composition layer, which is a resin composition layer (sheet), can be produced.

In producing the laminated sheet of the present embodiment, the temperature conditions for molding the layer of the (meth)acrylic resin composition by an extrusion molding method are the composition of the (meth)acrylic resin composition, the required (meth) It can be appropriately selected in consideration of the thickness of the layer of the acrylic resin composition. The temperature conditions for molding the layer of the (meth)acrylic resin composition are, for example, preferably 180 to 300°C, more preferably 200 to 290°C, and further preferably 220 to 280°C. preferable. The temperature is the temperature of the melt of the (meth)acrylic resin composition at the die lip of the die (or immediately after extrusion).

The melt of the resin composition for forming the base material layer can be extruded from a die in a heated state if necessary. In the production of the laminated sheet of the present embodiment, the temperature conditions for molding the base layer by extrusion molding include the components of the resin composition as the material, the blending ratio, the required thickness of the base layer, and the like. can be selected as appropriate. The temperature conditions for molding the substrate layer are preferably, for example, 180 to 300° C., more preferably 200 to 290° C., when the substrate layer is formed from a (meth)acrylic resin composition. More preferably, the temperature is 220 to 280°C. The temperature is the temperature of the molten resin composition at the die lip of the die (or immediately after extrusion).

The thickness of the (meth)acrylic resin composition layer in the laminated sheet of the present embodiment is not particularly limited. The thickness of the (meth)acrylic resin composition layer is antiviral, effectively suppresses the generation of static electricity and adhesion of dust, From the viewpoint of recovery of inhibition and transparency, the thickness 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. When the laminated sheet contains two or more layers of the (meth)acrylic resin composition, the thickness of the two or more (meth)acrylic resin composition layers may be the same or different. .

The thickness of the base material layer in the laminated sheet of this embodiment is not particularly limited. The thickness of the base material layer is preferably 0.05 mm or more and 4 mm or less, more preferably 0.1 mm or more and 3 mm or less, from the viewpoint of securing the hardness and strength of the laminated sheet.

<Evaluation method>
(1) Haze and its measurement method Haze (Haze 2mmt (%)) evaluated as a measure of transparency corresponds to JIS K 7136 (ISO14782, Plastics-Determination of haze for transparent materials.) can be measured according to A specific description will be given below.

First, the haze is 0.044 rad (2.5 °) Refers to the percentage of transmitted light deviated above.

In this embodiment, haze can be measured by any suitable conventionally known device (eg, haze meter HR-100 (manufactured by Murakami Color Laboratory)). Devices for measuring haze include, for example, devices with a stable light source, connecting optics, an integrating sphere with an aperture, and a photometer. The photometer preferably consists of a photodetector, a signal processor and a display or recorder.

A plurality of cut test pieces are usually used for haze measurement. The size of the specimen is not limited provided it is large enough to cover the entrance and compensation apertures of the integrating sphere.

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

Next, the device used for measurement is installed in an atmosphere maintained at a temperature of (23 ± 2) ° C. and a relative humidity of (50 ± 10)% as necessary, and a sufficient time has passed before measurement. Allow to reach thermal equilibrium.

Next, the test piece is placed in an apparatus, the luminous flux of the incident light transmitted through the test piece is observed, and the haze (%) is calculated by the following formula (3).

Haze = [(τ4/τ2) - τ3 (τ2/τ1)] × 100 (3)

In the above formula (3),
τ1 represents the luminous flux of incident light,
τ2 represents the total luminous flux transmitted through the test piece,
τ represents the luminous flux diffused in the device,
τ4 represents the luminous flux spread by the device and specimen.

(2) Surface resistivity and its measuring method The layer of the (meth)acrylic resin composition contained in the sheet and laminated sheet of the present embodiment has glycerin fatty acid ester, which is an active ingredient for antiviral properties, on the entire surface. Due to bleeding, the surface resistivity (Ω / sq) is reduced to at least less than 1.0E + 14 Ω / sq, the bleeding glycerin fatty acid ester is wiped off multiple times, and the surface resistivity is increased, the surface resistivity is reduced again by bleeding again the glycerin fatty acid ester a plurality of times each time. As a result, it is possible to maintain the antiviral properties and the effect of effectively suppressing the generation of static electricity on the surface of the shaped material and thus the adhesion of dust for a predetermined period of time.

In this embodiment, the surface resistivity is measured using a resistivity meter (e.g., Hiresta UP MCP-HT-450 manufactured by Mitsubishi Chemical Analytech Co., Ltd.), which is a conventionally known suitable measuring device. It can be measured according to K6911.

In measuring the surface resistivity, for example, after adjusting the condition by leaving it under the conditions of 23 ° C. and 50% RH for 24 hours, using the already described apparatus, by a method conforming to JIS K 6911 measurements can be made.

Examples of the present invention will be specifically described below. The invention is not limited by the examples described below.

Acrylic block copolymers (A-1) and (A-2), rubber particles (A-3), and acrylic block copolymer ( The PMMA (content) ratios of A-1) and (A-2) and the glass transition temperatures Tg (° C.) are as follows.
A-1: LA4285 (PMMA ratio: 50%) Tg -45.7°C
A-2: LA2270 (PMMA ratio: 40%) Tg -45°C
A-3: Rubber particles Tg -24.4°C
Acrylic block copolymers (A-1) and (A-2) were commercially available from Kuraray Co., Ltd. (block copolymers in which two PMMA blocks are bonded to both ends of a PnBA block). used
Rubber particles (A-3) used in Comparative Examples were produced and used as described in paragraph [0044] of Japanese Patent No. 54465432.

In addition, glycerin fatty acid esters (C-1) to (C-2), which are components (C) used in Examples and Comparative Examples to be described later, and their HLB values are as follows. All glycerin fatty acid esters were commercially available from Riken Vitamin Co., Ltd. and used.
C-1: DL-100 diglycerin monolaurate HLB value 9.4
C-2: M-300 glycerin monolaurate HLB value 5.4

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

[Production of compact (plate)]
The (meth)acrylic resin composition obtained as described above was placed in a frame mold with a thickness of 2 mm and preheated at 210° C. for 5 minutes. Next, press at a pressure of 2 MPa for 3 minutes, press at a pressure of 12 MPa for 1 minute, and then cool at room temperature at a pressure of 2 MPa for 1 minute to form a flat molded body (plate) (thickness: 2 mm). Obtained.

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

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

A sample of 50 mm x 50 mm cut from the plate manufactured as described above was left under conditions of 23°C and 50% RH for 24 hours. The surface resistivity of the plate was then measured.

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

[Measurement of surface resistivity immediately after wiping and 3 days after wiping]
The surface of the plate manufactured as described above was wiped (wiped) with Bencotton impregnated with special grade ethanol (sometimes referred to as the first wipe).

First, immediately after wiping, the surface resistivity of the wiped surface of the plate was measured. After wiping, the plate was left under conditions of 23° C. and 50% RH for 72 hours. The surface resistivity was then measured on the wiped surface of the plate.

[Measurement of surface resistivity immediately after second wiping and 3 days after wiping]
One day after the first wiping and measurement of the surface resistivity after 3 days of wiping performed as described above, the second wiping was performed in the same manner as the first wiping described above, immediately after wiping and 3 days after wiping. The measurement of the surface resistivity of was also carried out in the same manner.

<Examples 2 to 9>
The (meth)acrylic resin compositions of Examples 2 to 9 were prepared in the same manner as in Example 1 except that the composition was as shown in Table 1 below, and the haze was adjusted in the same manner as in Example 1. and surface resistivity were measured. The results are shown in Table 1 below.

<Comparative Examples 1 to 4>
(Meth)acrylic resin compositions according to Comparative Examples 1 to 4 were prepared in the same manner as in Example 1 except that the composition was as shown in Table 2 below, and the haze was adjusted in the same manner as in Example 1. and surface resistivity were measured. The results are shown in Table 2 below.

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 on the surface of the molded body, which has antiviral properties and further It was shown that the generation of static electricity and adhesion of dust due to the generation of static electricity can be suppressed.

In addition, according to Examples 1 to 9, which satisfy the requirements of the present invention, even if the glycerin fatty acid ester was repeatedly wiped off from the surface of the molded product by alcohol disinfection treatment multiple times, at least 3 days after wiping showed that the rebleeding of glycerin fatty acid ester to the surface could restore the antiviral properties, the generation of static electricity, and the effect of suppressing the adhesion of dust due to the generation of static electricity.

Furthermore, according to Examples 1 to 6 that satisfy the requirements of the present invention, the transparency can be further improved, and it can be suitably applied to applications that require transparency, and as a result, a wider range of applications It was shown that it can be applied to

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, the surface resistivity is reduced (imparted antiviral properties) and / or in wiping repeatedly once or twice or more It was shown that the reduction in surface resistivity (recovery of antiviral properties) by rebleeding multiple times could not be recovered.

The use of the molded material (molded article) obtained by molding the (meth)acrylic resin composition of the present invention is high in applications such as equipment and instruments that require antiviral properties, suppression of static electricity generation, and suppression of dust adhesion. have availability.

Claims (11)

1. 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 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 less, and the glycerin fatty acid ester is 100% by mass , the (meth)acrylic resin content is in the range of 35% by mass or more and 84% by 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. 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. acrylic block copolymer
   a methacrylate polymer block;
   4. The (meth)acrylic resin composition according to claim 3, which is a block copolymer containing an acrylate polymer block.
5. acrylic block copolymer
   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,
   5. The (meth)acrylic resin composition according to claim 4, which is a block copolymer having an acrylic acid ester polymer block content of 40% by mass or more and 70% by mass or less.
6. The (meth)acrylic resin composition according to any one of claims 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 claim 6, wherein the glycerin fatty acid ester is a glycerin saturated fatty acid ester.
8. A molded material obtained by molding the (meth)acrylic resin composition according to any one of claims 1 to 7.
9. The formed material according to claim 8, which is a sheet obtained by molding the (meth)acrylic resin composition.
10. A laminated sheet comprising one or more layers of the sheet according to claim 9.
11. Further comprising a substrate layer, the layer of the (meth)acrylic resin composition has the substrate layer on both the first main surface and the second main surface facing each other in the thickness direction of the substrate layer. 11. The laminated sheet according to claim 10, provided so as to sandwich.