Antistatic agent

Abstract

To provide a kneadable antistatic agent that can exhibit a superior antistatic effect regardless of the resin composition.SOLUTION: The present invention provides an antistatic agent for resin that contains a copolymer comprising at least one structural unit (i) having a double bond and a carboxyl group within its molecule, at least one structural unit (ii) having a double bond and a hydroxyl group within its molecule, and at least one structural unit (iii) having a double bond and a polyalkylene oxide group within its molecule.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to an antistatic agent. [Background technology]

[0002] As a method for preventing static electricity in resin molded products, antistatic agents have been developed that are kneaded into resin materials. For example, Patent Document 1 describes that a polymeric antistatic agent for thermoplastic resins containing a polyurethane compound does not lose its antistatic ability even after washing with water. Patent Document 2 describes that a combination of a specific anionic surfactant and a nonionic surfactant exhibits an excellent antistatic effect. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2018-178042 A [Patent Document 2] JP 2018-123306 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, conventional knead-in type antistatic agents sometimes do not have sufficient antistatic effect depending on the resin composition. Therefore, an object of the present invention is to provide a knead-in type antistatic agent that can exhibit good antistatic effect regardless of the resin composition. [Means for solving the problem]

[0005] The present invention provides the following [1] to

[13] . [1] An antistatic agent for resins, comprising a copolymer containing the following structural units (I) to (III): (I): A structural unit having at least one double bond and a carboxy group in the molecule. (II): A structural unit having at least one double bond and a hydroxyl group in the molecule. (III): A structural unit having at least one double bond and a polyalkylene oxide group in the molecule. [2] The antistatic agent according to [1], wherein the content of the structural unit (I) in the copolymer is 1 to 30 mol %. [3] The antistatic agent according to [1], wherein the content of the structural unit (II) in the copolymer is 20 to 95 mol %. [4] The antistatic agent according to [1], wherein the content of the structural unit (III) in the copolymer is 1 to 30 mol %. [5] The antistatic agent according to any one of [1] to [4], wherein the structural unit (II) is a structural unit represented by the following general formula (II-1): [ka] (In the formula, R 1 and R 2 each independently represents a hydrogen atom or an alkyl group, and m represents an integer of 0 to 20. [6] The antistatic agent according to any one of [1] to [5], wherein the structural unit (I) is a structural unit derived from acrylic acid and a salt thereof, and / or methacrylic acid and a salt thereof. [7] The antistatic agent according to any one of [1] to [6], wherein the structural unit (III) is a structural unit derived from a compound represented by the following formula (III-1) and / or (III-2): [ka] (In general formula (III-1), R 3 and R 4 Each of A and B independently represents a hydrogen atom or an alkyl group. 1 O is the same or different and represents an oxyalkylene group. n represents an integer of 0 to 200. In general formula (III-2), R 5 and R 6 Each of A and B independently represents a hydrogen atom or an alkyl group. p represents an integer of 0 to 2. 2O is the same or different and represents an oxyalkylene group. q represents an integer of 0 to 200. [8] A method for treating a resin surface, comprising kneading the antistatic agent according to any one of [1] to [7] into a resin substrate. [9] A resin composition comprising the antistatic agent according to any one of [1] to [7] and a resin substrate.

[10] The resin composition according to [9], wherein the content of the antistatic agent is 1.5% by weight or more based on 100% by weight of the resin substrate.

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

[10] , wherein the resin substrate further contains a cellulose-based material.

[12] A molded article made of the resin composition according to any one of [9] to

[11] .

[13] A method for producing a resin composition, comprising kneading the antistatic agent according to any one of [1] to [7] into a resin substrate. Effect of the Invention

[0006] According to the present invention, there is provided an antistatic agent that can exhibit a good antistatic effect regardless of the resin composition. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] [1. Antistatic agents for resins] The antistatic agent for resin contains the following copolymer as an active ingredient.

[0008] [1.1 Copolymer structural units] -Structural unit (I)- The structural unit (I) is a structural unit having at least one double bond and one carboxy group in the molecule. The number of double bonds and carboxy groups may be one or more, and either or both may be multiple, but preferably one of each.

[0009] The structural unit (I) is preferably a structural unit derived from an unsaturated carboxylic acid monomer (hereinafter referred to as monomer (i)). Examples of the unsaturated carboxylic acid monomer include monocarboxylic acid monomers and unsaturated dicarboxylic acid monomers. Examples of the unsaturated monocarboxylic acid monomer include acrylic acid, methacrylic acid, and crotonic acid. Examples of the unsaturated dicarboxylic acid include maleic acid, itaconic acid, citraconic acid, and fumaric acid. The structural unit (I) is preferably a structural unit derived from acrylic acid and methacrylic acid. The monomer (i) is preferably acrylic acid, methacrylic acid, and salts thereof, and more preferably acrylic acid, methacrylic acid, and salts thereof.

[0010] The structural unit (I) may be a structural unit derived from one type of monomer (i), or may be a structural unit derived from two or more types of monomer (i). When the structural unit (I) contains a structural unit (I-1) derived from acrylic acid and a structural unit (I-2) derived from methacrylic acid, the weight ratio of the structural unit (I-1) to the structural unit (I-2) (the total of (I-1) and (I-2) being 100% by weight) is usually (I-1) / (I-2)=(1% to 99%) / (99% to 1%), preferably (20% to 60%) / (80% to 40%), and more preferably (30% to 50%) / (50% to 70%).

[0011] -Structural unit (II)- The structural unit (II) is a structural unit having at least one double bond and hydroxyl group in the molecule. The number of double bonds and hydroxyl groups may be one or more, and either or both may be multiple, but preferably each is one. The structural unit (II) does not contain a polyalkylene oxide group. In this respect, it is distinguished from the structural unit (III).

[0012] The structural unit (II) is preferably a structural unit represented by the following general formula (II-1). [ka]

[0013] In general formula (II-1), R 1 and R 2 R each independently represents a hydrogen atom or an alkyl group. The number of carbon atoms in the alkyl group is usually 1 to 3, preferably 1 to 2, and more preferably 1. 1 and R 2 R is preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, more preferably a hydrogen atom or a methyl group. 1 and R 2 are each independent, i.e., may be the same or different.

[0014] m represents an integer of 0 to 20, and is usually 18 or less, 16 or less, 14 or less, preferably 12 or less, 10 or less, 8 or less, more preferably 6 or less, 4 or less. The lower limit is usually 0 or more, preferably 1 or more.

[0015] The structural unit (II) is preferably a unit derived from a monomer represented by general formula (ii-1).

[0016] [ka]

[0017] Each symbol in the general formula (ii-1) has the same definition as the corresponding symbol in the general formula (1), and the preferred examples are also the same.

[0018] The monomer represented by the general formula (ii-1) may be, for example, a monoester of an unsaturated monocarboxylic acid. Examples of the unsaturated monocarboxylic acid monoester include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate, and 2-hydroxyethyl (meth)acrylate and 2-hydroxypropyl (meth)acrylate are preferred.

[0019] The structural unit (II) may be a structural unit derived from one type of monomer (ii), or may be a structural unit derived from two or more types of monomer (ii). When 2-hydroxyethyl (meth)acrylate and 2-hydroxypropyl (meth)acrylate are used in combination as the monomer (ii), the weight ratio of 2-hydroxyethyl (meth)acrylate (ii-1) to 2-hydroxypropyl (meth)acrylate (ii-2) (the total of (ii-1) and (ii-2) is 100% by weight) is usually (i-1) / (i-2)=(1% to 99%) / (99% to 1%), preferably (30% to 70%) / (70% to 30%), more preferably (40% to 60%) / (60% to 40%).

[0020] -Structural unit (III)- The structural unit (III) is a structural unit having at least one double bond and one polyalkylene oxide group in the molecule. The number of the double bond and the polyalkylene oxide group may be one or more, and either or both may be multiple, but preferably one of each.

[0021] The structural unit (III) is preferably a structural unit represented by the following general formula (III-1) or (III-2). [ka]

[0022] In general formula (III-1), R 3 and R 4 R each independently represents a hydrogen atom or an alkyl group. The number of carbon atoms in the alkyl group is usually 1 to 3, preferably 1 to 2, and more preferably 1. 1 and R 2 is preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, more preferably a hydrogen atom or a methyl group; R 2 R is more preferably a hydrogen atom. 1 and R 2 are each independent, i.e., may be the same or different.

[0023] In the general formula (III-1), n ​​is the average number of moles of oxyethylene groups added. The average number of moles added means the average number of moles of alkylene glycol units added to 1 mole of a monomer. The lower limit of n is usually 1 or more, 2 or more, 3 or more, preferably 4 or more, 5 or more, 6 or more, more preferably 7 or more, 8 or more, 9 or more, and even more preferably 10 or more. The upper limit is usually 200 or less, 180 or less, preferably 150 or less, more preferably 120 or less, and even more preferably 100 or less. Therefore, n is usually 1 to 200, 2 to 200, 3 to 180, 4 to 160, 5 to 160, preferably 6 to 140, 7 to 140, 8 to 120, 9 to 120, 10 to 100, more preferably 6 to 140, 7 to 130, 8 to 120, 9 to 110, and even more preferably 10 to 100.

[0024] A in general formula (III-1) 1 O may be the same or different and represents an oxyalkylene group. The number of carbon atoms in the oxyalkylene group is usually 2 to 18, for example, 2 to 16, 2 to 14, 2 to 12, 2 to 10, or 2 to 8, preferably 2 to 6, and more preferably 2 to 4. Examples of the oxyalkylene group (alkylene glycol unit) include an oxyethylene group (ethylene glycol unit), an oxypropylene group (propylene glycol unit), and an oxybutylene group (butylene glycol unit). Among them, an oxyethylene group and an oxypropylene group are preferred, and an oxyethylene group is more preferred.

[0025] A 1 The term "same or different" in the definition of O means that A 1 If multiple Os are included (n is 2 or more), each A 1 This means that O may be the same oxyalkylene group or different (two or more types) oxyalkylene groups. 1In the case where a plurality of O's are contained, for example, there is a mixture of two or more oxyalkylene groups selected from the group consisting of oxyethylene groups (ethylene glycol), oxypropylene groups (propylene glycol) and oxybutylene groups (butylene glycol). A mixture of oxyethylene groups and oxypropylene groups or a mixture of oxyethylene groups and oxybutylene groups is preferred, and a mixture of oxyethylene groups and oxypropylene groups is more preferred. 1 In an embodiment containing a plurality of O, the addition of two or more types of oxyalkylene groups may be in a block form or a random form.

[0026] In general formula (III-2), R 5 and R 6 R each independently represents a hydrogen atom or an alkyl group. The number of carbon atoms in the alkyl group is usually 1 to 3, preferably 1 to 2, and more preferably 1. 5 and R 6 is preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, more preferably a hydrogen atom or a methyl group; R 6 R is more preferably a hydrogen atom. 5 and R 6 are each independent, i.e., may be the same or different.

[0027] In the general formula (III-2), p represents a number of 0 to 2, preferably 0 to 1, and more preferably 0.

[0028] In the general formula (III-2), q is the average number of moles of oxyethylene groups added. The lower limit of p is usually 1 or more, 2 or more, 3 or more, preferably 4 or more, 5 or more, 6 or more, more preferably 7 or more, 8 or more, 9 or more, and even more preferably 10 or more. The upper limit is usually 200 or less, 180 or less, preferably 150 or less, more preferably 120 or less, and even more preferably 100 or less. Therefore, q is usually 1 to 200, 2 to 200, 3 to 180, 4 to 160, 5 to 160, preferably 6 to 140, 7 to 140, 8 to 120, 9 to 120, 10 to 100, more preferably 6 to 140, 7 to 130, 8 to 120, 9 to 110, and even more preferably 10 to 100.

[0029] A in general formula (III-2) 2 O may be the same or different and represents an oxyalkylene group. The number of carbon atoms in the oxyalkylene group is usually 2 to 18, for example, 2 to 16, 2 to 14, 2 to 12, 2 to 10, or 2 to 8, preferably 2 to 6, and more preferably 2 to 4. Examples of the oxyalkylene group (alkylene glycol unit) include an oxyethylene group (ethylene glycol unit), an oxypropylene group (propylene glycol unit), and an oxybutylene group (butylene glycol unit). Among them, an oxyethylene group and an oxypropylene group are preferred, and an oxyethylene group is more preferred.

[0030] A 2 The term "same or different" in the definition of O means that A 2 If multiple Os are included (n is 2 or more), each A 2 This means that O may be the same oxyalkylene group or different (two or more types) oxyalkylene groups. 2In the case where a plurality of O's are contained, for example, there is a mixture of two or more oxyalkylene groups selected from the group consisting of oxyethylene groups (ethylene glycol), oxypropylene groups (propylene glycol) and oxybutylene groups (butylene glycol). A mixture of oxyethylene groups and oxypropylene groups or a mixture of oxyethylene groups and oxybutylene groups is preferred, and a mixture of oxyethylene groups and oxypropylene groups is more preferred. 2 In an embodiment containing a plurality of O, the addition of two or more types of oxyalkylene groups may be in a block form or a random form.

[0031] The structural unit (III) is preferably a unit derived from the monomer (iii-1) and / or (iii-2) represented by the general formula (iii-1) or (III-2). [ka]

[0032] Each symbol in the general formulae (iii-1) and (iii-2) has the same definition as that of each symbol in the general formulae (III-1) and (III-2), and preferred examples are also the same.

[0033] Examples of the monomer (iii-1) include esters of unsaturated carboxylic acids and (poly)alkylene glycols. Examples of the unsaturated carboxylic acids include (meth)acrylic acid. Examples of the (poly)alkylene glycols include (poly)ethylene glycol, (poly)ethylene (poly)propylene glycol, (poly)ethylene (poly)butylene glycol, methoxy (poly)ethylene glycol, methoxy (poly)ethylene (poly)propylene glycol, and methoxy (poly)ethylene (poly)butylene glycol.

[0034] Examples of the esters of unsaturated carboxylic acids and (poly)alkylene glycols include (poly)alkylene glycol (meth)acrylates such as (poly)ethylene glycol (meth)acrylate, (poly)ethylene (poly)propylene glycol (meth)acrylate, and (poly)ethylene (poly)butylene glycol (meth)acrylate; and methoxy(poly)alkylene glycol (meth)acrylates such as methoxy(poly)ethylene glycol (meth)acrylate, methoxy(poly)ethylene (poly)propylene glycol (meth)acrylate, and methoxy(poly)ethylene (poly)butylene glycol (meth)acrylate. Among these, (poly)alkylene glycol (meth)acrylate and methoxy(poly)ethylene glycol (meth)acrylate are preferred, and methoxy(poly)ethylene glycol (meth)acrylate is more preferred.

[0035] An example of a method for producing an ester of an unsaturated carboxylic acid and a (poly)alkylene glycol is a method of esterifying a (poly)alkylene glycol with an unsaturated monocarboxylic acid.

[0036] Examples of the monomer (iii-2) include polyalkylene glycol monoalkenyl ethers. Examples of the polyalkylene glycol monoalkenyl ethers include (poly)ethylene glycol (meth)allyl ether, (poly)ethylene glycol 3-methyl-3-butenyl ether, (poly)ethylene glycol (poly)propylene glycol (meth)allyl ether, (poly)ethylene (poly)propylene glycol (meth)allyl ether, (poly)ethylene (poly)propylene glycol 3-methyl-3-butenyl ether, (poly)ethylene (poly)butylene glycol (meth)allyl ether, (poly)ethylene (poly)butylene glycol Examples of the alkoxy 3-methyl-3-butenyl ether include methoxy (poly) ethylene glycol (meth) allyl ether, methoxy (poly) ethylene glycol 3-methyl-3-butenyl ether, methoxy (poly) ethylene (poly) propylene glycol (meth) allyl ether, methoxy (poly) ethylene (poly) propylene glycol 3-methyl-3-butenyl ether, methoxy (poly) ethylene (poly) butylene glycol (meth) allyl ether, and methoxy (poly) ethylene (poly) butylene glycol 3-methyl-3-butenyl ether. Among these, from the viewpoint of the balance between hydrophilicity and hydrophobicity, (poly) ethylene glycol (meth) allyl ether, (poly) ethylene glycol (poly) propylene glycol (meth) allyl ether, (poly) ethylene (poly) propylene glycol (meth) allyl ether, (poly) ethylene glycol 3-methyl-3-butenyl ether, and (poly) ethylene (poly) propylene glycol 3-methyl-3-butenyl ether are preferred.

[0037] Examples of methods for producing polyalkylene glycol monoalkenyl ethers include, but are not limited to, methods of adding an alkylene oxide to an unsaturated alcohol such as allyl alcohol, methallyl alcohol, or 3-methyl-3-buten-1-ol.

[0038] In this specification, "(meth)allyl" means both allyl and methallyl. "(meth)acrylate" means both acrylate and methacrylate. When (poly) is attached to the name of a compound, it means that the following substituent is singular or plural.

[0039] The structural unit (III) may be a structural unit derived from one type of monomer (iii), or may be a structural unit derived from two or more types of monomer (iii). In the case of a combination of two or more types of monomer (iii), it is preferable that the combination contains at least the monomer (iii-1).

[0040] -Examples of structural units other than those represented by the above general formulas (II-1), (III-1), and (III-2)- The copolymer may contain structural units other than the structural units represented by general formulae (II-1), (III-1), and (III-2), which are specific examples of the structural units. Examples of such structural units include structural units derived from the following monomers. The following specific examples may be contained in the copolymer regardless of whether they are included in the category of structural units (I) to (III). These structural units may be contained in the copolymer alone or in combination of two or more types.

[0041] A monomer represented by general formula (IV-1): [ka]

[0042] Examples of the monomer represented by the general formula (IV-1) include 3- and 3'-allyl-substituted bisphenols such as 4,4'-dihydroxydiphenylpropane, 4,4'-dihydroxydiphenylmethane, and 4,4'-dihydroxydiphenylsulfone.

[0043] A monomer represented by general formula (IV-2): [ka]

[0044] Examples of the monomer represented by the above general formula (IV-2) include 3-allyl-substituted bisphenols such as 4,4'-dihydroxydiphenylpropane, 4,4'-dihydroxydiphenylmethane, and 4,4'-dihydroxydiphenylsulfone.

[0045] A monomer represented by general formula (IV-3): [ka]

[0046] An example of the monomer represented by the general formula (IV-3) is allylphenol.

[0047] Half esters and diesters of unsaturated dicarboxylic acids, such as maleic acid, maleic anhydride, fumaric acid, itaconic acid, and citraconic acid, with alcohols having 1 to 30 carbon atoms;

[0048] Half amides and diamides of the above unsaturated dicarboxylic acids with amines having 1 to 30 carbon atoms;

[0049] half esters, half amides, diesters and diamides of (poly)oxyalkylene alkyl ethers or (poly)oxyalkylene alkyl amines in which 1 to 500 moles of alkylene oxide having 2 to 18 carbon atoms are added to alcohols or amines having 1 to 30 carbon atoms, and unsaturated dicarboxylic acids such as (meth)acrylic acid;

[0050] Half esters and diesters of the above unsaturated dicarboxylic acids with glycols having 2 to 18 carbon atoms or polyalkylene glycols having 2 to 500 moles of such glycols added;

[0051] Half amides of maleamic acid and glycols having 2 to 18 carbon atoms or polyalkylene glycols having 2 to 500 moles of such glycols added;

[0052] (poly)ethylene glycol mono(meth)acrylate, (poly)propylene glycol mono(meth)acrylate, (poly)butylene glycol mono(meth)acrylates (excluding monomer (iii)) in which 1 to 500 moles of alkylene oxide having 2 to 18 carbon atoms are added to unsaturated monocarboxylic acids such as (meth)acrylic acid;

[0053] (poly)alkylene glycol di(meth)acrylates such as triethylene glycol di(meth)acrylate, (poly)ethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, and (poly)ethylene glycol (poly)propylene glycol di(meth)acrylate;

[0054] Polyfunctional (meth)acrylates such as hexanediol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, and trimethylolpropane di(meth)acrylate;

[0055] (Poly)alkylene glycol dimaleates such as triethylene glycol dimaleate and polyethylene glycol dimaleate;

[0056] unsaturated sulfonic acids such as vinyl sulfonate, (meth)allyl sulfonate, 2-(meth)acryloxyethyl sulfonate, 3-(meth)acryloxypropyl sulfonate, 3-(meth)acryloxy-2-hydroxypropyl sulfonate, 3-(meth)acryloxy-2-hydroxypropyl sulfophenyl ether, 3-(meth)acryloxy-2-hydroxypropyloxysulfobenzoate, 4-(meth)acryloxybutyl sulfonate, (meth)acrylamidomethyl sulfonic acid, (meth)acrylamidoethyl sulfonic acid, 2-methylpropanesulfonic acid (meth)acrylamide, and styrenesulfonic acid, as well as their monovalent metal salts, divalent metal salts, ammonium salts, and organic amine salts;

[0057] Amides of unsaturated monocarboxylic acids and amines having 1 to 30 carbon atoms, such as methyl (meth)acrylamide;

[0058] vinyl aromatics such as styrene, α-methylstyrene, vinyltoluene, and p-methylstyrene;

[0059] Alkanediol mono(meth)acrylates such as 1,4-butanediol mono(meth)acrylate, 1,5-pentanediol mono(meth)acrylate, and 1,6-hexanediol mono(meth)acrylate;

[0060] Dienes such as butadiene, isoprene, 2-methyl-1,3-butadiene, and 2-chloro-1,3-butadiene;

[0061] Unsaturated amides such as (meth)acrylamide, (meth)acrylalkylamide, N-methylol (meth)acrylamide, and N,N-dimethyl (meth)acrylamide;

[0062] Unsaturated cyanides such as (meth)acrylonitrile and α-chloroacrylonitrile;

[0063] Unsaturated esters such as vinyl acetate and vinyl propionate;

[0064] Unsaturated amines such as aminoethyl (meth)acrylate, methylaminoethyl (meth)acrylate, dimethylaminoethyl (meth)acrylate, dimethylaminopropyl (meth)acrylate, dibutylaminoethyl (meth)acrylate, and vinylpyridine;

[0065] Divinyl aromatics such as divinylbenzene; cyanurates such as triallyl cyanurate;

[0066] Allyls such as (meth)allyl alcohol and glycidyl (meth)allyl ether;

[0067] Vinyl ethers or allyl ethers such as methoxypolyethylene glycol monovinyl ether, polyethylene glycol monovinyl ether, methoxypolyethylene glycol mono(meth)allyl ether, and polyethylene glycol mono(meth)allyl ether;

[0068] Siloxane derivatives such as polydimethylsiloxane propylaminomaleamic acid, polydimethylsiloxane aminopropylene aminomaleamic acid, polydimethylsiloxane bis-(propylaminomaleamic acid), polydimethylsiloxane bis-(dipropyleneaminomaleamic acid), polydimethylsiloxane-(1-propyl-3-acrylate), polydimethylsiloxane-(1-propyl-3-methacrylate), polydimethylsiloxane bis-(1-propyl-3-acrylate), and polydimethylsiloxane bis-(1-propyl-3-methacrylate).

[0069] The copolymer may have only one type of structural unit (IV), or may have two or more types of structural units (IV) derived from mutually different monomers.

[0070] In the copolymer, each of the structural units (I) to (IV) may be a structural unit composed of one type of monomer, or a structural unit composed of a combination of two or more types of monomers. Among these, the copolymer is preferably a copolymer which is a combination of the structural unit (I) and the structural unit (II), or a copolymer which is a combination of the structural units (I) to (III).

[0071] [1.2 Composition ratio of each structural unit of the copolymer] When the total of the structural units is 100 mol %, the composition ratio of each structural unit is, for example, as follows. The composition ratio below usually coincides with the blending amount of the monomer from which each structural unit is derived when producing the copolymer.

[0072] The content of the structural unit (I) is usually 1 mol% or more, preferably 3 mol% or more, more preferably 5 mol% or more. The upper limit is usually 40 mol% or less, preferably 35 mol% or less, more preferably 30 mol% or less. Therefore, it is usually 1 to 40 mol%, preferably 3 to 35 mol%, more preferably 5 to 30 mol%.

[0073] The content of the structural unit (II) is usually 20 mol% or more, preferably 25 mol% or more, more preferably 30 mol% or more. The upper limit is usually 95 mol% or less, preferably 92 mol% or less, more preferably 90 mol% or less. Therefore, it is usually 20 to 95 mol%, preferably 25 to 92 mol%, more preferably 30 to 90 mol%.

[0074] The content of the structural unit (III) is usually 1 mol% or more, preferably 3 mol% or more, more preferably 5 mol% or more. The upper limit is usually 30 mol% or less, preferably 25 mol% or less, more preferably 20 mol% or less. Therefore, it is usually 1 to 30 mol%, preferably 3 to 25 mol%, more preferably 5 to 20 mol%.

[0075] When a structural unit other than the structural units (I) to (III) is contained, the content thereof is usually 30 mol % or less, preferably 25 mol % or less, and more preferably 20 mol % or less. There is no particular lower limit, and it is sufficient as long as it is 0 mol % or more.

[0076] [1.3 Copolymer salt] The copolymer may be in the form of a salt, for example, a monovalent metal salt, a divalent metal salt, an ammonium salt, or an organic amine salt of the copolymer.

[0077] [1.4 Physical properties of copolymers] -Weight average molecular weight- The weight average molecular weight of the copolymer is usually 5,000 or more, preferably 10,000 or more, more preferably 15,000 or more, and even more preferably 20,000 or more. This can satisfactorily improve the dispersibility as an agricultural chemical additive. The upper limit is usually 200,000 or less, preferably 150,000 or less, more preferably 130,000 or less, and even more preferably 100,000 or less. This can suppress aggregation and avoid deterioration of workability. Therefore, it is usually 5,000 to 200,000, preferably 10,000 to 150,000, more preferably 15,000 to 130,000, and even more preferably 20,000 to 100,000.

[0078] -Mw / Mn- The molecular weight distribution (Mw / Mn) of the polycarboxylic acid copolymer or a salt thereof is preferably 1.2 to 3.0, more preferably 1.4 to 2.5, and further preferably 1.5 to 2.0.

[0079] The weight average molecular weight in the present invention can be measured by a known method using gel permeation chromatography (GPC) in terms of polyethylene glycol.

[0080] Examples of GPC measurement conditions include the following conditions. The weight average molecular weight in the examples below is a value measured under these conditions. Measuring device: Tosoh Columns used: Shodex Column OH-pak SB-806HQ, SB-804HQ, SB-802.5HQ Eluent: 0.05 mM sodium nitrate / acetonitrile 8 / 2 (v / v) Standard material: Polyethylene glycol (Tosoh, GL Science) Detector: Differential refractometer (manufactured by Tosoh) Calibration curve; Polyethylene glycol standard

[0081] [1.5 Method for producing copolymer] The method for producing the copolymer may be a method for copolymerizing the monomers from which each structural unit is derived. Examples of such a method include polymerization methods such as polymerization in a solvent and bulk polymerization. The monomers from which each structural unit is derived preferably include a combination of monomers (i), (ii), and (iii-1) and / or (iii-2). Each monomer may be a salt (e.g., monovalent metal salt, ammonium salt, organic amine salt) or anhydride.

[0082] Examples of the solvent used in the polymerization in a solvent include water, lower alcohols such as methyl alcohol, ethyl alcohol, isopropyl alcohol, etc., aromatic hydrocarbons such as benzene, toluene, xylene, etc., aliphatic hydrocarbons such as cyclohexane, n-hexane, etc., esters such as ethyl acetate, etc., ketones such as acetone, methyl ethyl ketone, etc. From the viewpoint of the solubility of the raw material monomers and the resulting copolymer, it is preferable to use one or more selected from the group consisting of water and lower alcohols, and among them, it is more preferable to use water.

[0083] When copolymerization is carried out in a solvent, each monomer and the polymerization initiator may be continuously added dropwise to a reaction vessel, or a mixture of each monomer and the polymerization initiator may be continuously added dropwise to a reaction vessel. Alternatively, a solvent may be charged into a reaction vessel, and a mixture of the monomers and the solvent and a polymerization initiator solution may be continuously added into the reaction vessel, or a part or all of the monomers may be charged into a reaction vessel, and the polymerization initiator may be continuously added dropwise.

[0084] Examples of polymerization initiators that can be used in copolymerization include persulfates such as ammonium persulfate, sodium persulfate, and potassium persulfate when copolymerization is performed in an aqueous solvent; and water-soluble organic peroxides such as t-butyl hydroperoxide. In this case, accelerators such as sodium hydrogen sulfite and Mohr's salt can be used in combination. In addition, when copolymerization is performed in a solvent such as a lower alcohol, an aromatic hydrocarbon, an aliphatic hydrocarbon, an ester, or a ketone, for example, peroxides such as benzoyl peroxide and lauryl peroxide; hydroperoxides such as cumene peroxide; and aromatic azo compounds such as azobisisobutyronitrile can be used as polymerization initiators. In this case, accelerators such as amine compounds can be used in combination. Furthermore, when copolymerization is performed in a water-lower alcohol mixed solvent, the above-mentioned polymerization initiators or combinations of polymerization initiators and accelerators can be appropriately selected and used. The polymerization temperature varies depending on the polymerization conditions such as the solvent used and the type of polymerization initiator, but is usually performed in the range of 50 to 120°C.

[0085] In the copolymerization, the molecular weight can be adjusted by using a chain transfer agent as necessary. Examples of the chain transfer agent used include known thiol compounds such as mercaptoethanol, thioglycerol, thioglycolic acid, 2-mercaptopropionic acid, 3-mercaptopropionic acid, thiomalic acid, octyl thioglycolate, and 2-mercaptoethanesulfonic acid; phosphorous acid, hypophosphorous acid, and salts thereof (sodium hypophosphite, potassium hypophosphite, etc.), sulfurous acid, hydrogen sulfite, dithionous acid, metabisulfite, and salts thereof (sodium sulfite, potassium sulfite, sodium hydrogen sulfite, potassium hydrogen sulfite, sodium dithionite, potassium dithionite, sodium metabisulfite, potassium metabisulfite, etc.), and lower oxides and salts thereof. These may be used alone or in combination of two or more. Furthermore, a monomer (V) with high chain transfer properties (for example, a (meth)allylsulfonic acid (salt)-based monomer) may be used to adjust the molecular weight of the copolymer. The content of the monomer (V) in the polycarboxylic acid copolymer or its salt (A) is usually 20% by weight or less, and preferably 10% by weight or less. The above content is the content when the content of the monomer (I) + content of the monomer (II) + content of the monomer (III) + content of the monomer (IV) = 100% by weight.

[0086] When copolymerization is performed in an aqueous solvent to obtain a copolymer, the pH during polymerization is usually strongly acidic due to the influence of the monomer having an unsaturated bond, but this may be adjusted to an appropriate pH. If pH adjustment is required during polymerization, the pH can be adjusted using an acidic substance such as phosphoric acid, sulfuric acid, nitric acid, alkyl phosphoric acid, alkyl sulfuric acid, alkyl sulfonic acid, or (alkyl)benzenesulfonic acid. Among these acidic substances, phosphoric acid is preferably used because of its pH buffering effect. However, in order to eliminate the instability of the ester bond of the ester monomer, it is preferable to perform polymerization at a pH of 2 to 7. There is no particular limitation on the alkaline substance that can be used to adjust the pH, but alkaline substances such as NaOH and Ca(OH)2 are common. The pH adjustment may be performed on the monomer before polymerization, or on the copolymer solution after polymerization. In addition, a part of the alkaline substance may be added before polymerization to perform polymerization, and then the pH of the copolymer may be further adjusted.

[0087] [1.6 Optional components of antistatic agents] The antistatic agent may contain an optional component other than the copolymer, such as an antistatic component other than the copolymer, a solvent, an emulsifier (surfactant: nonionic, anionic, amphoteric, cationic), an antioxidant, a heat stabilizer, a light stabilizer, an ultraviolet absorber, a flame retardant, a plasticizer, a pigment, a dye, a dye dispersant, a chelating agent, unreacted compounds (i) and (ii), etc.

[0088] [2. How to use antistatic agents] The antistatic agent can be used to prevent static electricity in resins. As a method for obtaining an antistatic effect in resins, for example, a method of kneading the antistatic agent into a resin base material containing a resin material can be mentioned.

[0089] [2.1 Resin materials] The resin material may be either a thermoplastic resin or a thermosetting resin, but is preferably a thermoplastic resin. For example, polyolefin resins such as polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, and ethylene-ethyl acrylate copolymer, halogen-containing resins such as polyvinyl chloride, polyvinylidene chloride, polyvinylidene fluoride, and polytetrafluoroethylene, styrene-based resins such as polyacrylonitrile, polystyrene, and copolymers of styrene and other monomers (for example, acrylonitrile-styrene (AS) resin, acrylonitrile-butadiene-styrene (ABS) resin), polyester-based resins such as polyester, polyethylene terephthalate, polybutylene terephthalate, and unsaturated polyester, acrylic resins such as polyacrylic and polymethyl methacrylate, epoxy resins, phenol-based resins, polyamide-based resins, polyimide-based resins, polysulfone resins, polyvinyl alcohol, polyurethane resins, polycarbonate resins, polydimethylsiloxane resins, and combinations thereof may be used, and may be either synthetic resins or natural resins. The resin substrate may be made of one type of resin or a combination of two or more types of resins.

[0090] [2.2 Cellulosic materials] The resin substrate may contain a cellulose-based material. By adding an antistatic agent to a resin material containing a cellulose-based material, it is possible to expect an antistatic effect as well as an improvement in cellulose dispersibility. Examples of the cellulose-based material include cellulose powder, cellulose fibers (cellulose nanofibers, cellulose microfibrils), pulp, and modified products thereof (for example, modified products obtained by chemical modification such as oxidation, etherification, phosphate esterification, silane coupling, fluorination, and cationization).

[0091] When the cellulose-based material is a cellulose powder, the average particle size is preferably 20 μm or more, more preferably 25 μm or more, and even more preferably 30 μm or more. This makes it possible to suppress scattering and improve mixability when the cellulose powder is added to a reaction system. The upper limit is preferably 100 μm or less, more preferably 80 μm or less, and even more preferably 60 μm or less. This makes it possible to maintain the kneadability during the formation of an ion complex and the smoothness of the resulting ion complex. Therefore, the average particle size of the cellulose powder is preferably 20 to 100 μm, more preferably 25 to 80 μm, and even more preferably 30 to 60 μm.

[0092] In this specification, the average particle size is the particle size when the volume accumulation distribution is 50%. The volume accumulation distribution can be obtained by a laser scattering method. The measuring device and measuring conditions are as follows. Measurement equipment: Laser diffraction particle size distribution measurement equipment (Mastersizer 3000, Spectris, Inc., Malvern Panalytical Division) Measurement conditions: Add a sample to the measurement section in water stirred at 3500 rpm so that the scattering intensity is about 10%, and measure under the following conditions. Analysis: General Purpose Analysis Sensitivity: Emphasis Light scattering model: Mie theory

[0093] The apparent specific gravity of the cellulose powder is preferably 0.1 g / ml or more, more preferably 0.15 g / ml or more. This can suppress the deterioration of workability due to scattering when the cellulose powder is added to the reaction system. The upper limit is preferably 0.6 g / ml or less, more preferably 0.45 g / ml or less, and even more preferably 0.4 g / ml or less. This can suppress the deterioration of dispersibility due to the occurrence of precipitation when the cellulose powder is added to the reaction system. Therefore, the range of 0.1 to 0.6 g / ml is preferable, the range of 0.1 to 0.45 g / ml is more preferable, and the range of 0.15 to 0.4 g / ml is even more preferable.

[0094] In this specification, the apparent specific gravity is the mass of cellulose powder per unit volume (1 mL). The apparent specific gravity can be measured, for example, by putting a sample (e.g., 10 g) into a measuring cylinder (e.g., 100 mL capacity), tapping the bottom of the measuring cylinder until the height of the sample stops decreasing, measuring the volume by reading the scale on the flattened surface, and dividing the weight of the sample by the volume.

[0095] The resin substrate may be a resin substrate having a biomass degree. For example, a resin substrate containing a resin material containing a plant-derived resin material such as plant-derived polyethylene, polypropylene, or polyester may be used. The biomass degree can be adjusted by further including a cellulose component. The biomass degree is as follows: 14 This is the concentration of C and can be measured by accelerator mass spectrometry.

[0096] [2.3 Other added ingredients] The resin substrate may contain additives other than the cellulose-based material. Examples of the additives include known resin additives such as antioxidants, preservatives, stabilizers, solvents, and inorganic fillers (e.g., carbon fiber, talc, mica, titanium oxide, and silica), and are not particularly limited.

[0097] [2.4 Usage] The amount of antistatic agent used (amount of copolymer relative to 100% by weight of the resin substrate (including additive components, the same applies below)) is usually 1.0% by weight or more, preferably 1.5% by weight or more or 2.0% by weight or more, more preferably 2.5% by weight or more. The upper limit is usually 80% by weight or less, preferably 75% by weight or less, more preferably 70% by weight or less. Therefore, it is usually 1.0 to 80% by weight, preferably 1.5 to 80% by weight or 2.0 to 75% by weight, more preferably 2.5 to 70% by weight.

[0098] When the resin substrate contains a cellulose-based material, the ratio of the content of the cellulose-based material to the content of the resin substrate is usually 5 / 95 or more, preferably 10 / 90 or more, more preferably 15 / 85 or more. The upper limit is usually 80 / 20 or less, preferably 75 / 25 or less, more preferably 70 / 30 or less.

[0099] The above composition usually corresponds to the amount of each component blended when the composition is produced.

[0100] [2.5 Mixing method] The method of kneading (blending) the antistatic agent into the resin substrate is not particularly limited, and any commonly used method can be used. When kneading, a kneading machine may be used as necessary. When kneading, the system may be heated, and the heating temperature is, for example, 100°C or higher, preferably 150°C or higher. The upper limit is usually 250°C or lower, preferably 200°C or lower.

[0101] [2.6 Resin compositions, molded products] A resin composition containing an antistatic agent and a resin substrate can exhibit antistatic properties, and by molding the resin composition, a molded article having a good antistatic effect can be obtained. Examples of applications of the molded article include electronic parts (e.g., household appliances, trays for transporting semiconductors). EXAMPLES

[0102] The present invention will be described in more detail below with reference to examples, but the present invention is not limited thereto.

[0103] Example 1 In a 3L separable flask, 300 parts of water, 25 parts of polyethylene glycol monoallyl ether (average number of moles of ethylene oxide added: 10), and 59 parts of polyethylene glycol monomethacrylate (average number of moles of ethylene oxide added: 25) were added, and the mixture was heated and stirred to 100°C. Then, a monomer solution containing 11 parts of acrylic acid, 98 parts of 2-hydroxypropyl acrylate, and 100 parts of water, and a mixture of 1 part of ammonium persulfate and 44 parts of water were added continuously over 2 hours, and the mixture was held for 1 hour to obtain copolymer a-1. The pH of this solution was adjusted to 4 with a 30% NaOH aqueous solution to obtain an aqueous solution of copolymer a-1. The weight average molecular weight of copolymer a-1 was 20,000 (Table 1).

[0104] Example 2 300 parts of water and 102 parts of polyethylene glycol monoacrylate (average mole number of ethylene oxide added: 10) were added to a 3L separable flask, and the mixture was heated and stirred until it reached 100°C. Then, a monomer solution of 26 parts of methacrylic acid, 65 parts of 2-hydroxypropyl acrylate, and 100 parts of water, and a mixture of 1 part of ammonium persulfate and 44 parts of water were added continuously over 2 hours, and the mixture was held for 1 hour to obtain copolymer a-2. The pH of this solution was adjusted to 4 with a 30% NaOH aqueous solution to obtain an aqueous solution of copolymer a-2. The weight average molecular weight of copolymer a-2 was 30,000 (Table 1).

[0105] Example 3 In a 3L separable flask, 300 parts of water, 174 parts of polyethylene glycol monoallyl ether (average number of moles of ethylene oxide added: 25), and 77 parts of polyethylene glycol monoacrylate (average number of moles of ethylene oxide added: 10) were added, and the mixture was heated and stirred to 100°C. Then, a monomer solution containing 7 parts of acrylic acid, 69 parts of 2-hydroxyethyl acrylate, and 100 parts of water, and a mixture of 1 part of ammonium persulfate and 44 parts of water were added continuously over 2 hours, and the mixture was held for 1 hour to obtain copolymer a-3. The pH of this solution was adjusted to 4 with a 30% NaOH aqueous solution to obtain an aqueous solution of copolymer a-3. The weight average molecular weight of copolymer a-3 was 40,000 (Table 1).

[0106] Example 4 In a 3L separable flask, 600 parts of water, 223 parts of polyethylene glycol monoallyl ether (average number of moles of ethylene oxide added: 100), and 117 parts of polyethylene glycol monoacrylate (average number of moles of ethylene oxide added: 25) were added, and the mixture was heated and stirred to 100°C. After that, a monomer solution containing 7 parts of acrylic acid, 13 parts of methacrylic acid, 35 parts of 2-hydroxyethyl acrylate, 39 parts of 2-hydroxypropyl acrylate, and 200 parts of water, and a mixture of 1 part of ammonium persulfate and 44 parts of water were added continuously over 2 hours, and the mixture was held for 1 hour to obtain copolymer a-4. The pH of this liquid was adjusted to 4 with a 30% NaOH aqueous solution to obtain an aqueous solution of copolymer a-4. The weight average molecular weight of copolymer a-4 was 100,000 (Table 1).

[0107] Example 5 300 parts of water and 25 parts of polyethylene glycol monoallyl ether (average number of moles of ethylene oxide added: 10) were added to a 3L separable flask, and the mixture was heated and stirred until it reached 100°C. Then, a monomer solution of 22 parts of acrylic acid, 75 parts of 2-hydroxyethyl acrylate, and 100 parts of water, and a mixture of 1 part of ammonium persulfate and 44 parts of water were added continuously over 2 hours, and the mixture was held for 1 hour to obtain copolymer a-5. The pH of this solution was adjusted to 4 with a 30% NaOH aqueous solution to obtain an aqueous solution of copolymer a-5. The weight average molecular weight of copolymer a-5 was 25,000 (Table 1).

[0108] Example 6 900 parts of water and 224 parts of polyethylene glycol monoacrylate (average mole number of ethylene oxide added: 100) were added to a 3L separable flask, and the mixture was heated and stirred until it reached 100°C. Then, a monomer solution of 4 parts of acrylic acid, 117 parts of 2-hydroxypropyl acrylate, and 300 parts of water, and a mixture of 1 part of ammonium persulfate and 44 parts of water were added continuously over 2 hours, and the mixture was held for 1 hour to obtain copolymer a-6. The pH of this solution was adjusted to 4 with a 30% NaOH aqueous solution to obtain an aqueous solution of copolymer a-6. The weight average molecular weight of copolymer a-6 was 60,000 (Table 1).

[0109] Example 7 In a 3L separable flask, 900 parts of water, 116 parts of polyethylene glycol monoallyl ether (average number of moles of ethylene oxide added: 25), and 119 parts of polyethylene glycol monomethacrylate (average number of moles of ethylene oxide added: 25) were added, and the mixture was heated and stirred to 100°C. Then, a monomer solution containing 22 parts of methacrylic acid, 72 parts of 2-hydroxypropyl acrylate, and 100 parts of water, and a mixture of 1 part of ammonium persulfate and 44 parts of water were added continuously over 2 hours, and the mixture was held for 1 hour to obtain copolymer a-7. The pH of this liquid was adjusted to 4 with a 30% NaOH aqueous solution to obtain an aqueous solution of copolymer a-7. The weight average molecular weight of copolymer a-7 was 50,000 (Table 1).

[0110] Example 8 Into a 3L separable flask, 1000 parts of water, 25 parts of polyethylene glycol monoallyl ether (average number of moles of ethylene oxide added: 10), 26 parts of polyethylene glycol monomethacrylate (average number of moles of ethylene oxide added: 10), and 224 parts of polyethylene glycol monomethacrylate (average number of moles of ethylene oxide added: 100) were added, and the mixture was heated and stirred to 100°C. After that, a monomer solution containing 11 parts of acrylic acid, 91 parts of 2-hydroxypropyl acrylate, and 100 parts of water, and a mixture of 1 part of ammonium persulfate and 44 parts of water were added continuously over 2 hours, and the mixture was held for 1 hour to obtain copolymer a-8. The pH of this liquid was adjusted to 4 with a 30% NaOH aqueous solution to obtain an aqueous solution of copolymer a-8. The weight average molecular weight of copolymer a-8 was 80,000 (Table 1).

[0111] Comparative Example 1 100 parts of water was added to a 1L separable flask, and the mixture was heated and stirred until it reached 100°C. A monomer solution of 14 parts of acrylic acid, 104 parts of 2-hydroxypropyl acrylate, and 300 parts of water, and a mixture of 1 part of ammonium persulfate and 44 parts of water were added continuously over 2 hours, and the mixture was held for 1 hour to obtain copolymer a-9. The pH of this solution was adjusted to 4 with a 30% NaOH aqueous solution to obtain an aqueous solution of copolymer a-9. The weight average molecular weight of copolymer a-9 was 20,000 (Table 1).

[0112] Comparative Example 2 In a 3L separable flask, 600 parts of water and 234 parts of polyethylene glycol monoacrylate (average number of moles of ethylene oxide added: 25) were added, and the mixture was heated and stirred until it reached 100°C. Then, a monomer solution of 104 parts of 2-hydroxypropyl acrylate and 300 parts of water, and a mixture of 1 part of ammonium persulfate and 44 parts of water were added continuously over 2 hours, and the mixture was held for 1 hour to obtain copolymer a-10. The pH of this solution was adjusted to 4 with a 30% NaOH aqueous solution to obtain an aqueous solution of copolymer a-10. The weight average molecular weight of copolymer a-10 was 100,000 (Table 1).

[0113] [Table 1]

[0114] [Notes to Table 1] AA: Acrylic acid MAA: Methacrylic acid HEA: 2-hydroxyethyl acrylate HPA: 2-hydroxypropyl acrylate Ar: Polyethylene glycol monoallyl ether Ac: Polyethylene glycol monoacrylate Mac: Polyethylene glycol monomethacrylate EO10: Average number of moles of ethylene oxide added: 10 EO25: Average number of moles of ethylene oxide added: 25 EO100: Average number of moles of ethylene oxide added: 100

[0115] [Preparation of kneaded base material] Polypropylene resin pellets, Wintech (registered trademark) WSX-03 (propylene-ethylene copolymer manufactured by Japan Polypropylene), cellulose powder, KC Flock W-100GK (manufactured by Nippon Paper Industries Co., Ltd.), and additives were mixed in a Labo Plastomill (registered trademark) (4M150; manufactured by Toyo Seiki Co., Ltd.) at a temperature of 180°C and a rotation speed of 150 rpm for 5 minutes to obtain a mixed base material, so that the total weight of the mixture was 40 g in terms of solid content.

[0116] As the additive, one of the following types was used. Sample solutions prepared in the examples and comparative examples Compatibilizer resin (Eumex 1010, Sanyo Chemical) Antistatic resin (Pellestat 300, Sanyo Chemical)

[0117] When the additive contained moisture, it completely evaporated during kneading and was released outside the system.

[0118] The resulting kneaded base material was rolled at a temperature of 200° C. and a pressure of 5 MPa for 1 minute to obtain a test piece having a smooth surface and a size of about 10 cm square and a thickness of about 1 mm.

[0119] [Evaluation of cellulose dispersibility] The obtained test pieces were observed under a microscope, and objects having a length of 2.5 mm or more and an aspect ratio of 100 or more were determined to be unmixed cellulose fibers. The observation conditions were as follows: Observed with a field of view of 8mm square, magnification of 35x, and resolution of 5.2μm. · Different areas on the test specimen were observed five times in total, and the amount of unmixed cellulose fibers observed was counted.

[0120] The evaluation criteria are as follows: "Good": The number of unmixed cellulose fibers is 0 in a total of 5 observations. "△": 1 to 3 unmixed cellulose fibers were observed in 1 to 3 observations. "X": Three or more unmixed cellulose fibers were observed in one to three observations, or one or more unmixed cellulose fibers were observed in three or more observations.

[0121] [Measurement of surface resistivity] Measurements were performed using a high resistivity meter "Hi-Resta-UP" (manufactured by Mitsubishi Chemical) in accordance with JIS K 6911. A test piece made from the kneaded base material was placed on the Teflon (registered trademark) surface of a register table UFL (manufactured by Mitsubishi Chemical) as a measurement table under conditions of a temperature of 25°C and a humidity of 50%, and a URS probe (manufactured by Mitsubishi Chemical) was used as a probe, and the probe was lightly pressed against the center of the test piece and the measured value was recorded after 10 seconds. The above measurement was performed a total of five times for the same sample so that the measurement points did not overlap, and the average value was taken as the surface resistivity (Ω / sq.).

[0122] 〔comprehensive evaluation〕 The evaluation of cellulose dispersibility and the measurement results of surface resistivity were combined to give an overall evaluation according to the following criteria. "Good": The cellulose dispersibility is evaluated as "good" and the measured surface resistivity is 5.0×10 12 below. "△": The cellulose dispersibility is rated "△" and the measured surface resistivity is 5.0×10 12 or less, or the cellulose dispersibility is evaluated as "good" but the measured surface resistivity is 5.0×10 12 ~2.0×10 13 Range. "×": Cellulose dispersibility is rated "×" and / or the measured surface resistivity is 2.0×10 13 Exceeds.

[0123] An overall rating of △ or above indicates that the product is practical.

[0124] The cellulose dispersibility, surface resistivity and overall evaluation results of the obtained kneaded base material are shown in Table 2.

[0125] [Table 2]

[0126] In the kneaded base material of only cellulose and PP without additives, neither cellulose dispersibility nor surface resistivity was practical.In addition, in the copolymer of a monomer having at least one double bond and a carboxyl group in a molecule and a monomer having at least one double bond and a hydroxyl group in a molecule (Comparative Example 1), or in the copolymer of only a monomer having at least one double bond and a hydroxyl group and a polyalkylene oxide compound having at least one double bond in a molecule (Comparative Example 2), neither cellulose dispersibility nor surface resistivity was improved to a practical level.

[0127] In addition, the use of only the compatibilizer additive improves cellulose dispersibility but does not improve surface resistivity, and the use of only the antistatic additive improves surface resistivity but does not improve cellulose dispersibility, so that both performance properties cannot be achieved at the same time.

[0128] On the other hand, when the additives of Examples 1 to 8 were added, a small amount of the additives reduced the surface resistivity, and some of them exceeded the amount of the existing antistatic resins. In addition, when the additives were added to a substrate containing cellulose, the cellulose dispersibility was confirmed by increasing the amount of each additive.

[0129] These results show that the composition of the present invention can improve surface resistivity, and when the resin composition contains a cellulose component, it is expected that the cellulose dispersibility can also be improved, and therefore the composition can be used in products for electronic components and environmentally friendly products.

Claims

1. An antistatic agent for resins, comprising a copolymer containing the following structural units (I) to (III): (I): A structural unit having at least one double bond and one carboxy group in the molecule. (II): A structural unit having at least one double bond and one hydroxyl group in the molecule. (III): A structural unit having at least one double bond and a polyalkylene oxide group in the molecule.

2. 2. The antistatic agent according to claim 1, wherein the content of the structural unit (I) in the copolymer is 1 to 30 mol %.

3. 2. The antistatic agent according to claim 1, wherein the content of the structural unit (II) in the copolymer is 20 to 95 mol %.

4. 2. The antistatic agent according to claim 1, wherein the content of the structural unit (III) in the copolymer is 1 to 30 mol %.

5. The antistatic agent according to any one of claims 1 to 4, wherein the structural unit (II) is a structural unit represented by the following general formula (II-1): 【Chemistry 1】 (In the formula, R １ and R ２ each independently represents a hydrogen atom or an alkyl group; and m represents an integer of 0 to 20.

6. 5. The antistatic agent according to claim 1, wherein the structural unit (I) is a structural unit derived from acrylic acid and a salt thereof, and / or methacrylic acid and a salt thereof.

7. The antistatic agent according to any one of claims 1 to 4, wherein the structural unit (III) is a structural unit derived from a compound represented by the following formula (III-1) and / or (III-2): 【Chemistry 2】 (In general formula (III-1), R ３ and R ４ each independently represents a hydrogen atom or an alkyl group. １ O is the same or different and represents an oxyalkylene group. n is an integer of 0 to 200. In general formula (III-2), R ５ and R ６ Each of A and B independently represents a hydrogen atom or an alkyl group. p represents an integer of 0 to 2. ２ O is the same or different and represents an oxyalkylene group; and q represents an integer of 0 to 200.

8. A method for treating a resin surface, comprising kneading the antistatic agent according to any one of claims 1 to 4 into a resin substrate.

9. A resin composition comprising the antistatic agent according to any one of claims 1 to 4 and a resin substrate.

10. The resin composition according to claim 9, wherein the content of the antistatic agent is 1.5% by weight or more based on 100% by weight of the resin substrate.

11. The resin composition of claim 9 , wherein the resin substrate further comprises a cellulosic material.

12. A molded article made from the resin composition according to claim 9.

13. A method for producing a resin composition, comprising kneading the antistatic agent according to any one of claims 1 to 4 into a resin substrate.

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