Composition containing methyl methacrylate and method of production of methyl methacrylate polymer

Abstract

composition containing methyl methacrylate and method for producing methyl methacrylate polymer. The present invention relates to a composition containing methyl methacrylate with high quality stability during storage. This can be achieved with a composition containing methyl methacrylate, an α,β-unsaturated carbonyl compound represented by the following formula (1) and a polymerization inhibitor, in which the concentration of methyl methacrylate is 99 to 99.99% by mass.

Description

Descriptive Report of the Invention Patent for COMPOSITION CONTAINING METHYL METHACRYLATE AND METHOD FOR PRODUCING METHYL METHACRYLATE POLYMER. TECHNICAL FIELD

[001] The present invention relates to a composition containing methyl methacrylate and to a method for producing methyl methacrylate polymer. PREVIOUS TECHNIQUE

[002] Methyl methacrylate (hereinafter also referred to as Methyl methacrylate (MMA) is known to be an extremely useful substance used as a raw material for various applications and types of polymers. For example, polymethyl methacrylate, a homopolymer of methyl methacrylate, is used in signage, lighting equipment, automotive parts, construction-related materials, light-guiding panels for flat displays, light diffusion plates, and the like, taking advantage of its excellent transparency, weather resistance, and other properties. Furthermore, copolymers of methyl methacrylate and other monomers are used in paints, adhesives, resin modifiers, artificial marble, paper latex, and the like.Several methods have been developed for the industrial production of methyl methacrylate, and for example, the acetone cyanohydrin (ACH) method, the novel acetone cyanohydrin (new ACH) method, the C4 direct oxidation method, the direct methyl esterification method, the ethylene method, and the novel ethylene method are known (Non-Patent Document 1). In these production methods, methyl methacrylate of suitable quality for the intended use is obtained by performing purification, such as distillation, to remove unreacted raw materials and by-products contained in the methyl methacrylate produced.

[003] Because methyl methacrylate has a tendency to polymerize, Petition 870230094863, dated 10 / 26 / 2023, page 8 / 91 2 / 58 It is known that the quality of methyl methacrylate is maintained by the addition of a polymerization inhibitor when producing methyl methacrylate or storing produced methyl methacrylate (Non-Patent Document 2). For example, Patent Document 1 describes that hydroquinone methyl ether (MEHQ) is particularly preferred among several polymerization inhibitors. Patent Document 2 describes that N,N'-dialkyl-p-phenylenediamine and N-oxyl are preferable among several polymerization inhibitors. Patent Document 3 describes the distillation of methyl methacrylate in the presence of a phenol polymerization inhibitor. Patent Document 4 describes the use of a diphenylamine derivative as a polymerization inhibitor. Patent Document 5 describes the use of a benzene triamine derivative as a polymerization inhibitor. Prior Art Documents PATENT DOCUMENTS

[004] Patent Document 1: JP 2004-155757A

[005] Patent Document 2: JP 2005-502695A

[006] Patent Document 3: JP H10-504553 A

[007] Patent Document 4: JP 2002-533309A

[008] Patent Document 5: JP 2002-513034A NON-PATENT DOCUMENTS

[009] Non-Patent Document 1: Toru Kuroda, Development of Catalyst for Producing Methyl Methacrylate', Catalysts & Catalysis, 45 (5), 366-371, 2003, Catalysis Society of Japan

[0010] Non-Patent Document 2: Takayuki Otsu, "On the Functions of Polymerization Inhibitors", Synthetic Organic Chemistry, 33 (8), 634-640, 1975, The Society of Synthetic Organic Chemistry, Japan SUMMARY OF THE INVENTION PROBLEMS TO BE SOLVED BY THE INVENTION

[0011] However, even in cases where they are added Petition 870230094863, dated 10 / 26 / 2023, page 9 / 91 3 / 58 polymerization inhibitors as described above, the quality of methyl methacrylate may deteriorate during storage. Considering the above circumstances, the objective of the present invention is to provide a composition containing methyl methacrylate with high-quality stability during storage. WAYS TO SOLVE THE PROBLEMS

[0012] To achieve the above objectives, the present inventors have studied intensively. As a result, they have discovered that, in methyl methacrylate with deteriorated quality during storage, the concentration of methyl methacrylate is reduced and methyl methacrylate and methyl pyruvate dimers are produced. The presence of methyl methacrylate dimers in methyl methacrylate can alter the structure of the methyl methacrylate polymer obtained by polymerization, adversely affecting its physical properties. Furthermore, the presence of methyl pyruvate in methyl methacrylate causes discoloration of the methyl methacrylate polymer obtained by polymerization.The present inventors have discovered that the inclusion of an α,β-unsaturated carbonyl compound represented by a specific structural formula in a composition containing methyl methacrylate results in improved quality stability during storage and reduced production of methyl methacrylate and methyl pyruvate dimers, thus completing the present invention.

[0013] Consequently, the present invention provides the following [1] to

[33] :

[0014] [1]: A composition containing methyl methacrylate, comprising methyl methacrylate, an α,β-unsaturated carbonyl compound represented by the following Formula (1) (component A1), and a polymerization inhibitor (component B), Petition 870230094863, dated 10 / 26 / 2023, page 10 / 91 4 / 58 where the concentration of methyl methacrylate is 99 to 99.99% by mass, R3 where, in Formula (1) above, R1, R2 and R3 each independently represent a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, a hydroxyl group, an alkoxy group, an amino group, a monovalent group containing a carbonyl group, an alkylthio group, or an arylthio group; R4 represents an alkyl group, an alkenyl group, an aryl group, a hydroxyl group, an alkoxy group, an amino group, a monovalent group containing a carbonyl group, an alkylthio group, or an arylthio group; R1 and R2, R2 and R3 and R4 can be linked together to form a ring, except when R1 = H, R2 = H, R3 = CH3 and R4 = OCH3, that is, when the α,β-unsaturated carbonyl compound represented by Formula (1) is methyl methacrylate; and H represents a hydrogen atom, O represents a carbon atom, and O represents an oxygen atom;

[0015] [2]: The composition containing methyl methacrylate, according to [1], wherein when the concentration of component A1 is MA1 (pmol / L) and the concentration of component B is MB (pmol / L), MB / MA1 is 0.1 or more;

[0016] [3]: The composition containing methyl methacrylate, according to [1] or [2], wherein when the concentration of component A1 is MA1 (pmol / L), MA1 is from 1 to 85,000 pmol / L;

[0017] [4]: ​​The composition containing methyl methacrylate, according to [3], wherein MA1 is 10 to 40,000 pmol / L; Petition 870230094863, dated 10 / 26 / 2023, page 11 / 91 5 / 58

[0018] [5]: The composition containing methyl methacrylate, according to any one of [1] to [4], wherein when the concentration of component B is MB (μmol / L), MB is from 1 to 7,000 pmol / L;

[0019] [6]: The composition containing methyl methacrylate, according to [5], wherein the MB is 10 to 5,000 μmol / L;

[0020] [7]: The composition containing methyl methacrylate, according to any one of [1] to [6], wherein the molecular weight of component A1 is 1,000 or less;

[0021] [8]: The composition containing methyl methacrylate, according to any one of [1] to [7], wherein component B is at least one polymerization inhibitor selected from the group consisting of a phenol compound, a quinone compound, a nitrobenzene compound, an N-oxyl compound, an amine compound, a phosphorus-containing compound, a sulfur-containing compound, an iron-containing compound, a copper-containing compound and a manganese-containing compound;

[0022] [9] The composition containing methyl methacrylate, according to any one of [1] to [8], wherein component B is at least one polymerization inhibitor selected from the group consisting of a phenol compound, an N-oxyl compound, an amine compound, a phosphorus-containing compound and a sulfur-containing compound;

[0023]

[10] : The composition containing methyl methacrylate, according to any one of [1] to [9], wherein component B is at least one polymerization inhibitor selected from the group consisting of hydroquinone, 4-methoxyphenol, 2,4-dimethyl-6-t-butylphenol, 2,6-di-t-butyl4-methylphenol, 4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl, N,N-diphenylamine, N-nitrosodiphenylamine, triphenyl phosphite and phenothiazine;

[0024]

[11] : The composition containing methyl methacrylate, according to [1], wherein in Formula (1) above, R1, R2 and R3 are each independently a hydrogen atom, a C1-5 alkyl group, Petition 870230094863, dated 10 / 26 / 2023, page 12 / 91 6 / 58 is a C2-5 alkenyl group, a C1-12 aryl group, a C1-6 alkoxy group, an amino group, a monovalent group containing a carbonyl group, or a C1-5 alkylthio group; and R4 is a C1-5 alkyl group, a C2-5 alkenyl group, a C1-12 aryl group, a hydroxyl group, a C1-6 alkoxy group, an amino group, a monovalent group containing a carbonyl group, or a C1-5 alkylthio group;

[0025]

[12] : The composition containing methyl methacrylate, according to any one of [1] to

[11] , wherein in Formula (1) above, R1, R2 and R3 are each independently a hydrogen atom or a C1-5 alkyl group; R4 is a C1-5 alkyl group or a C15 alkoxy group;

[0026]

[13] : The composition containing methyl methacrylate, according to any one of [1] to

[12] , wherein in Formula (1) above, R1, R2 and R3 are each independently a hydrogen atom, a methyl group, an ethyl group, an n-propyl group or an isopropyl group; and R4 is a methyl group, a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, an isobutoxy group or an isopentoxy group;

[0027]

[14] : The composition containing methyl methacrylate, according to any one of [1] to

[13] , wherein the concentration of methyl methacrylate is from 99.8 to 99.99% by mass;

[0028]

[15] : The composition containing methyl methacrylate, according to any one of [1] to

[14] , wherein the composition does not contain diacetyl, or the concentration of diacetyl contained is 55 μmol / L or less;

[0029]

[16] : Composition containing methyl methacrylate, comprising: methyl methacrylate; and an α,β-unsaturated carboxylate ester represented by the following Formula (2) (component A2), where Petition 870230094863, dated 10 / 26 / 2023, p. 13 / 91 7 / 58 the concentration of methyl methacrylate is 99 to 99.99% by mass, and

[0030] when the concentration of component A2 is MA2 (μmol / L), MA2 is 1 to 40,000 pmol / L; R7(2) R5O where, in Formula (2) above, R5, R6, and R7 each independently represent a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, a hydroxyl group, an alkoxy group, an amino group, a monovalent group containing a carbonyl group, an alkylthio group, or an arylthio group. R8 represents an alkyl group, an alkenyl group, or an aryl group. R5 and R6, R6 and R7, R7 and R8 can be linked together to form a ring, except when R5= H, R6= H, R7= CH3 and R8= CH3, that is, when the α,β-unsaturated carbonyl compound represented by Formula (2) is methyl methacrylate, and

[0031] H represents a hydrogen atom, C represents a carbon atom and O represents an oxygen atom;

[0032]

[17] : The composition containing methyl methacrylate, according to

[16] , where MA2 is 10 to 5,000 pmol / L;

[0033]

[18] : The composition containing methyl methacrylate, according to

[16] or

[17] , where MA2 is 10 to 500 pmol / L;

[0034]

[19] : The composition containing methyl methacrylate, according to any one of

[16] to

[18] , wherein the molecular weight of component A2 is 1,000 or less;

[0035]

[20] : The composition containing methyl methacrylate, according to any one of

[16] to

[19] , where in Formula (2) above, Petition 870230094863, dated 10 / 26 / 2023, p. 14 / 91 8 / 58 R5, R6 and R7 are each independently a hydrogen atom, a C1-5 alkyl group, a C2-5 alkenyl group, a C1-12 aryl group, a C1-6 alkoxy group, an amino group, a monovalent group containing a carbonyl group, or a C1-5 alkylthio group; and R8 is a C1-5 alkyl group, a C2-5 alkenyl group, or a C1-12 aryl group;

[0036]

[21] : The composition containing methyl methacrylate, according to any one of

[16] to

[20] , wherein in Formula (2) above, R5, R6 and R7 are each independently a hydrogen atom or a C1-5 alkyl group, and R8 is a C1-5 alkyl group;

[0037]

[22] : The composition containing methyl methacrylate, according to any one of

[16] to

[21] , wherein in Formula (2) above, R5, R6, and R7 are each, independently, a hydrogen atom, a methyl group, an ethyl group, an n-propyl group, or an isopropyl group, and R8 is a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, or an isopentyl group;

[0038]

[23] : The composition containing methyl methacrylate, according to any one of

[16] to

[22] , wherein in Formula (2) above, R5, R6, and R7 are each, independently, either a hydrogen atom or a methyl group, and R8 is a methyl group;

[0039]

[24] : The composition containing methyl methacrylate, according to any one of

[16] to

[23] , wherein the concentration of methyl methacrylate is from 99.8 to 99.99% by mass;

[0040]

[25] : The composition containing methyl methacrylate, according to any one of

[16] to

[24] , wherein the composition does not contain diacetyl, or Petition 870230094863, dated 10 / 26 / 2023, page 15 / 91 9 / 58 the concentration of diacetyl contained is equal to or less than 55 μmol / L;

[0041]

[26] Composition containing methyl methacrylate, comprising: methyl methacrylate; and at least one compound (component A3) selected from the group consisting of methyl acrylate, butyl acrylate, ethyl methacrylate, methyl crotonate, cis-methyl crotonate, isobutyl methacrylate, butyl methacrylate, propyl methacrylate, isopentyl methacrylate, methyl 2-methylene-3-butenoate, methyl 3,3-dimethylacrylate, methyl 2-ethylacrylate, methyl 2-pentenoate, methyl cinnamate, methyl 3-methoxyacrylate, dimethyl fumarate, methyl 1-cyclohexene-1-carboxylate, methacrylamide, acrylic acid, crotonic acid, cis-crotonic acid, 3,3-dimethylacrylic acid, 2-ethylacrylic acid, 2-methylene-3-butenoic acid and trans-3-hexen-2-one, in that

[0042] the concentration of methyl methacrylate is 99 to 99.99% by mass, and when the concentration of component A3 is MA3 (pmol / L), MA3 is 1 to 40,000 pmol / L;

[0043]

[27] : The composition containing methyl methacrylate, according to

[26] , wherein MA3 is 10 to 5,000 μmol / L;

[0044]

[28] : The composition containing methyl methacrylate, according to

[26] or

[27] , wherein the MA3 is 10 to 500 μmol / L;

[0045]

[29] : The composition containing methyl methacrylate, according to any one of

[26] to

[28] , wherein component A3 is at least one selected from the group consisting of methyl acrylate, methyl crotonate, acrylic acid and crotonic acid;

[0046]

[30] : The composition containing methyl methacrylate, according to any one of

[26] to

[29] , wherein the concentration of methyl methacrylate is from 99.8 to 99.99% by mass; Petition 870230094863, dated 10 / 26 / 2023, page 16 / 91 10 / 58

[0047]

[31] : The composition containing methyl methacrylate, according to any one of

[26] to

[30] , wherein the composition does not contain diacetyl, or the concentration of diacetyl contained is equal to or less than 55 μmol / L;

[0048]

[32] : A method for producing a methyl methacrylate polymer, comprising a polymerization step of a polymeric composition comprising a composition containing methyl methacrylate, according to any one of [1] to

[31] ; and

[0049]

[33] : The method for producing a methyl methacrylate polymer according to

[32] , wherein the polymer composition comprises 0.01% by mass or more of a monomer that can be copolymerized with methyl methacrylate relative to 100 parts by mass of methyl methacrylate. EFFECT OF THE INVENTION

[0050] According to the present invention, a composition containing methyl methacrylate can be provided having high-quality stability with reduced production of methyl methacrylate dimer and methyl pyruvate during storage. DETAILED DESCRIPTION OF THE INVENTION

[0051] Embodiments of the present invention will be described below, but the present invention is not limited to them.

[0052] As used in this document, any range of numerical values ​​indicated by the term up to means any range including numerical values ​​described before and after the term up to as the lower and upper limit values, respectively, and A to B means A or more and B or less. Composition 1 containing methyl methacrylate

[0053] A composition containing methyl methacrylate in a first aspect according to the present invention comprises Petition 870230094863, dated 10 / 26 / 2023, page 17 / 91 11 / 58 methyl methacrylate, an α,β-unsaturated carbonyl compound represented by the following Formula (1) (component A1) and a polymerization inhibitor (component B), wherein the concentration of methyl methacrylate is 99 to 99.99% by mass. R3

[0054] In Formula (1) above, R1, R2 and R3 each independently represent a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, a hydroxy group, an alkoxy group, an amino group, a monovalent group containing a carbonyl group, an alkylthio group or an arylthio group. R4 represents an alkyl group, an alkenyl group, an aryl group, a hydroxy group, an alkoxy group, an amino group, a monovalent group containing a carbonyl group, an alkylthio group or an arylthio group. R1 and R2, R2 and R3, and R3 and R4 may be linked together to form a ring, except when R1= H, R2= H, R3= CH and R4= OCH3, that is, when the α,β-unsaturated carbonyl compound represented by Formula (1) is methyl methacrylate. H represents a hydrogen atom, C represents a carbon atom, and O represents an oxygen atom.

[0055] The composition containing methyl methacrylate may also contain another compound (component C) or water, provided that the composition satisfies a methyl methacrylate concentration of 99 to 99.99% by mass. Each item will be described in detail below. Component A1

[0056] The composition containing methyl methacrylate in the first aspect according to the present invention comprises an α,β-unsaturated carbonyl compound represented by Formula (1) described above (component A1). When component A1 and component B described below coexist, the production of methyl methacrylate and methyl pyruvate dimers during storage of Petition 870230094863, dated 10 / 26 / 2023, page 18 / 91 12 / 58 composition containing methyl methacrylate may be suppressed. The reason for this is presumed to be as follows.

[0057] Methyl methacrylate dimers are produced due to radicals generated during the storage of methyl methacrylate. Examples of radicals include hydroxyl radicals produced when oxygen molecules absorb ultraviolet light derived from sunlight. Hydroxyl radicals also cause the production of methyl pyruvate due to the oxidation of methyl methacrylate. The α,β-unsaturated carbonyl compound has a conjugated double bond and therefore absorbs ultraviolet light. The absorption wavelength varies depending on the type of substituent. The α,β-unsaturated carbonyl compound with a structure represented by Formula (1) described above can absorb ultraviolet light across a wide wavelength range. Therefore, when the methyl methacrylate-containing composition comprises a component A1, a wide wavelength range of ultraviolet light is absorbed and the production of hydroxyl radicals is reduced.Furthermore, by including component B described later, it is possible to capture the generated hydroxyl radicals. Thus, it is considered that when component A1 and component B coexist, the production of methyl methacrylate and methyl pyruvate dimers can be reduced. Among several organic compounds that absorb ultraviolet light, an α,β-unsaturated carbonyl compound has a molecular structure similar to that of methyl methacrylate, so that when producing a polymer using the composition containing methyl methacrylate as a raw material, adverse effects may occur. The inclusion of an α,β-unsaturated carbonyl compound as an impurity can be reduced.

[0058] The molecular weight of component A1 is preferably .000 or less. When the molecular weight is 1.000 or less, the number of conjugated double bonds per unit mass in component A1 can be increased, so that the effect of the present invention Petition 870230094863, dated 10 / 26 / 2023, p. 19 / 91 13 / 58 can be obtained with less mass. The molecular weight of component A1 is most preferably 800 or less, even more preferably 600 or less, and particularly preferably 400 or less.

[0059] In Formula (1) above, R1, R2 and R3 each independently represent a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, a hydroxy group, an alkoxy group, an amino group, a monovalent group containing a carbonyl group, an alkylthio group or an arylthio group. R4 in Formula (1) above represents an alkyl group, an alkenyl group, an aryl group, a hydroxy group, an alkoxy group, an amino group, a monovalent group containing a carbonyl group, an alkylthio group or an arylthio group. R1, R2, R3 and R4 may be the same or different from each other.

[0060] When R1, R2, R3 and R4 satisfy the conditions described above, the conjugated pi system in component A1 is maintained, and thus component A1 has the property of absorbing a wide wavelength of ultraviolet light, so that the effect of the present invention can be obtained. R1, R2 and R3 are each preferably a hydrogen atom, a C1-5 alkyl group, a C2-5 alkenyl group, a C1-12 aryl group, a C1-6 alkoxy group, an amino group, a monovalent group containing a carbonyl group, or a C1-5 alkylthio group. They are highly stable substituents and therefore can prevent component A1 from being transformed into other compounds during storage. When component A1 has such a substituent, a quantity of ultraviolet light absorbed by component A1 will suffice as a single molecule.R1, R2 and R3 are more preferably a hydrogen atom or a C1-5 alkyl group, and even more preferably a hydrogen atom, a methyl group, an ethyl group, an n-propyl group or an isopropyl group. R4 is preferably a C1-5 alkyl group, a C2-5 alkenyl group, a C1-12 aryl group, a... Petition 870230094863, dated 10 / 26 / 2023, p. 20 / 91 14 / 58 hydroxyl group, a C1-6 alkoxy group, an amino group, a monovalent group containing a carbonyl group, or a C1-5 alkylthio group. These are highly stable substituents and therefore can prevent component A1 from being transformed into other compounds during storage. R4 is more preferably a C1-5 alkyl group or a C1-5 alkoxy group, and even more preferably a methyl group, a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, an isobutoxy group, or an isopentoxy group. When R4 has the structure described above, the composition containing methyl methacrylate can have greater quality stability during storage.

[0061] The alkyl group is a chain alkyl group (linear or branched) or a cyclic alkyl group. The alkyl group is preferably a C1-20 alkyl group, more preferably a C1-10 alkyl group, and even more preferably a C1-5 alkyl group. Examples of chain alkyl groups include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, an s-butyl group, a t-butyl group, an n-pentyl group, an isopentyl group, a hexyl group, an octyl group, a decyl group, a hydroxymethyl group, a 1-hydroxyethyl group, and a 2-hydroxyethyl group; and a methyl group, an ethyl group, an n-propyl group, and an isopropyl group are preferred. Examples of cyclic alkyl groups include a cyclopentyl group, a cyclohexyl group, and a cyclooctyl group.

[0062] The alkenyl group is a chain alkenyl group (linear or branched) or a cyclic alkenyl group. The alkenyl group is preferably a C2-20 alkenyl group, more preferably a C2-10 alkenyl group, and even more preferably a C2-5 alkenyl group. Examples of chain alkenyl groups include a vinyl group, a 1-propenyl group, an isopropenyl group, a 2-butenyl group, a 1,3-butadienyl group, a 2-pentenyl group, and a 2-hexenyl group. Petition 870230094863, dated 10 / 26 / 2023, p. 21 / 91 15 / 58 Examples of cyclic alkenyl groups include cyclopentenyl groups and cyclohexenyl groups.

[0063] The aryl group is preferably a C1-20 aryl group and more preferably a C1-12 aryl group. The aryl group includes a heteroaryl group containing oxygen, nitrogen, sulfur or the like.Examples of aryl groups include a phenyl group, a mesityl group, a naphthyl group, a 2-methylphenyl group, a 3-methylphenyl group, a 4-methylphenyl group, a 2,3-dimethylphenyl group, a 2,4-dimethylphenyl group, a 2,5-dimethylphenyl group, a 2,6-dimethylphenyl group, a 2-ethylphenyl group, an isoxazolyl group, an isothiazolyl group, an imidazolyl group, an oxazolyl group, a thiazolyl group, a thiadiazolyl group, a thienyl group, a triazolyl group, a tetraazolyl group, a pyridyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a pyrazolyl group, a pyrrolyl group, a furyl group, a furazanyl group, an isoquinolyl group, an isoindolyl group, an indolyl group, a group quinoline, a pyridothiazolyl group, a benzimidazolyl group, a benzooxazolyl group, a benzothiazolyl group, a benzotriazolyl group, a benzofuranyl group, an imidazopyridinyl group, a triazopyridinyl group, and a purinyl group.

[0064] The alkoxy group is preferably a C1-20 alkoxy group, more preferably a C1-10 alkoxy group, and even more preferably a C1-6 alkoxy group. Examples of alkoxy groups include a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, an isobutoxy group, an s-butoxy group, a t-butoxy group, an n-pentoxy group, an isopentoxy group, and a phenoxy group.

[0065] The amino group includes an amine group without a substituent on the nitrogen atom (-NH2) and an amine group in which some or all of the hydrogen atoms bonded to the nitrogen atom are replaced by carbon atoms. The number of carbon atoms in an amine group substituted by carbon atoms is preferably Petition 870230094863, dated 10 / 26 / 2023, p. 22 / 91 16 / 58 to 20, more preferably from 1 to 10, and even more preferably from 1 to 5. Examples of the amino group include a methylamino group, an ethylamino group, a propylamino group, a butylamino group, a dimethylamino group, a diethylamino group, an anilino group, a toluidino group, an anisidino group, a diphenylamino group, and an N-methyl-N-phenylamino group.

[0066] Examples of monovalent groups containing a carbonyl group include a formyl group, an acyl group, a carboxy group, an amide group, an alkoxy carbonyl group, a thiocarboxy group, and a thioester group.

[0067] An acyl group is a substituent in which a carbonyl group is attached to an alkyl group, an alkenyl group, or an aryl group. The total number of carbon atoms derived from a carbonyl group (one) and derived from an alkyl group, an alkenyl group, or an aryl group is preferably from 2 to 20, more preferably from 2 to 10, and even more preferably from 2 to 6. Examples of acyl groups include an acetyl group, a propionyl group, a butylcarbonyl group, a vinylcarbonyl group, and a benzoyl group.

[0068] The amide group includes an amide group without a substituent on the nitrogen atom (-CONH2) and an amide group in which some or all of the hydrogen atoms bonded to the nitrogen atom are replaced by carbon atoms. The number of carbon atoms in the amide group, which is the total number of carbon atoms derived from a carbonyl group (one) and the number of carbon atoms substituted on the nitrogen atom, is preferably from 1 to 20, more preferably from 1 to 10, and even more preferably from 1 to 5. Examples of the amide group include an unsubstituted amide group, an N-methylamide group, an N-ethylamide group, an N-phenylamide group, an N,N-dimethylamide group, and an N-methyl-N-phenylamide group.

[0069] The alkoxy carbonyl group is a substituent in which a group Petition 870230094863, dated 10 / 26 / 2023, p. 23 / 91 17 / 58 carbonyl and an alkoxy group are linked, and also referred to as an ester group. The total number of carbon atoms derived from a carbonyl group (one) and derived from an alkoxy group is preferably from 2 to 20, more preferably from 2 to 10, and even more preferably from 2 to 6. Examples of the alkoxy carbonyl group include a methoxy carbonyl group, an ethoxy carbonyl group, a butoxy carbonyl group, and a phenoxy carbonyl group.

[0070] The thioester group is a substituent in which a carbonyl group and an alkylthio or arylthio group are attached. The total number of carbon atoms derived from a carbonyl group (one) and derived from an alkylthio or arylthio group is preferably from 2 to 20, more preferably from 2 to 10, and even more preferably from 2 to 6. Examples of the thioester group include a methylthiocarbonyl group, an ethylthiocarbonyl group, a butylthiocarbonyl group, and a phenylthiocarbonyl group.

[0071] The monovalent group containing a carbonyl group may be a substituent in which one or more hydrogen(s) in an alkyl group is / are replaced by one or more carbonyl groups. Examples of such a substituent include a 2-acetoxyethyl group, a 2-acetoethyl group, and a 2-(acetoacetoxy)ethyl group.

[0072] The alkylthio group is preferably a C1-20 alkylthio group, more preferably a C1-10 alkylthio group, and even more preferably a C1-5 alkylthio group. Examples of the alkylthio group include a methylthio group, an ethylthio group, a propylthio group, and an isopropylthio group.

[0073] The arylthio group is preferably a C1-20 arylthio group, more preferably a C3-10 arylthio group, and even more preferably a C6-10 arylthio group. Examples of the arylthio group include a phenylthio group and a tolylthio group.

[0074] R1and R2, R2and R3and R3and R4can be connected together to Petition 870230094863, dated 10 / 26 / 2023, p. 24 / 91 18 / 58 form a ring. Examples of compounds where R1 and R2 are linked to form a ring include methyl 2-cyclohexylidenepropionate and methyl 2-cyclopentylidenepropionate. Examples of compounds where R2 and R3 are linked to form a ring include methyl 1-cyclohexene-1-carboxylate and methyl 1-cyclopentene-1-carboxylate. Examples of compounds where R3 and R4 are linked to form a ring include α-methylene-δ-valerolactone and α-methylene-γ-butyrolactone.

[0075] Among the compounds that satisfy the conditions described above, component A1 is preferably methyl acrylate, butyl acrylate, ethyl methacrylate, methyl crotonate, cis-methyl crotonate, isobutyl methacrylate, butyl methacrylate, propyl methacrylate, isopentyl methacrylate, methyl 2-methylene-3-butenoate, methyl 3,3-dimethylacrylate, methyl 2-ethylacrylate, methyl 2-pentenoate, methyl cinnamate, methyl 3-methoxyacrylate, dimethyl fumarate, methacrylamide, acrylic acid, methacrylic acid, crotonic acid, cis-crotonic acid, 3,3-dimethylacrylic acid, 2-ethylacrylic acid, 2-methylene-3-butenoic acid, trans-3-hexen-2-one, isopropenyl methyl ketone, methyl 2-cyclohexylidenepropionate, methyl 2-cyclopentylidenepropionate, methyl 1-cyclohexene-1-carboxylate, methyl 1-cyclopentene-1-carboxylate, α-methyleneδ-valerolactone, α-methylene-γ-butyrolactone or isopropenyl methyl ketone, more preferably methyl acrylate,butyl acrylate, ethyl methacrylate, methyl crotonate, cis-methyl crotonate, isobutyl methacrylate, butyl methacrylate, propyl methacrylate, isopentyl methacrylate, methyl 2-methylene-3-butenoate, methyl 3,3-dimethylacrylate, methyl 2-ethylacrylate, methyl 2-pentenoate, methyl cinnamate, methyl 3-methoxyacrylate, dimethyl fumarate, methyl 1-cyclohexene-1-carboxylate, methacrylamide, acrylic acid, methacrylic acid, crotonic acid, cis-crotonic acid, 3,3-dimethylacrylic acid, 2-ethylacrylic acid, 2-methylene-3-butenoic acid, trans-3-hexen-2-one, or isopropenyl methyl ketone, and even more preferably methyl acrylate, ethyl methacrylate, Petition 870230094863, dated 10 / 26 / 2023, page 25 / 91 19 / 58 methyl crotonate, isobutyl methacrylate, butyl methacrylate, propyl methacrylate, isopentyl methacrylate, 3,3-dimethylacrylate and isopropenyl methyl ketone from the point of view of quality stability of the composition containing methyl methacrylate during storage.

[0076] One or two or more component(s) A1 may be contained in the composition containing methyl methacrylate in the first aspect according to the present invention. Component B

[0077] The composition containing methyl methacrylate in a first aspect according to the present invention comprises a polymerization inhibitor (component B). As used herein, the term polymerization inhibitor means a compound that has the function of inhibiting the polymerization reaction of methyl methacrylate. Examples of polymerization inhibitors include a phenol compound, a quinone compound, a nitrobenzene compound, an N-oxyl compound, an amine compound, a phosphorus-containing compound, a sulfur-containing compound, an iron-containing compound, a copper-containing compound, and a manganese-containing compound. When component B is included, the progress of the methyl methacrylate polymerization reaction through a radical polymerization mechanism during the storage of methyl methacrylate can be suppressed. Component B can also retain the hydroxyl radicals generated during the storage of methyl methacrylate.That is, when the composition containing methyl methacrylate comprises component A1 as well as component B, the hydroxyl radical content can be reduced through two different mechanisms: one in which component A1 can reduce the production of hydroxyl radicals, and the other in which component B can remove the hydroxyl radicals produced. Thus, the production of... is considered. Petition 870230094863, dated 10 / 26 / 2023, p. 26 / 91 20 / 58 methyl methacrylate and methyl pyruvate dimers can be efficiently reduced.

[0078] Examples of polymerization inhibitors that are phenol compounds include alkylphenol, hydroxyphenol, aminophenol, nitrophenol, nitrosophenol, alkoxyphenol, and tocopherol.

[0079] Examples of alkylphenols include o-cresol, m-cresol, p-cresol, 2-t-butyl-4-methylphenol, 2,4-dimethyl-6-t-butylphenol, 2,6-di-t-butyl-4-methylphenol, 2-t-butylphenol, 4-t-butylphenol, 2,4-di-t-butylphenol, 2-methyl-4-t-butylphenol, 4-tbutyl-2,6-dimethylphenol, 2,2 '-methylene-bis(6-t-butyl-4-methylphenol), 2,2'-methylenebis(4-ethyl-6-t-butylphenol), 4,4'-thiobis(3-methyl-6-t-butylphenol) and 3,5-di-tbutyl-4-hydroxytoluene.

[0080] Examples of hydroxyphenol include hydroquinone, 2-methylhydroquinone, 2-t-butylhydroquinone, 2,5-di-t-butylhydroquinone, 2,6-di-t-butylhydroquinone, 2,5-di-t-amylhydroquinone, 2-t-butylmethoxyhydroquinone, 2,3,5-trimethylhydroquinone, 2,5-dichlorohydroquinone, 1,2-dihydroxybenzene, 2-acetylhydroquinone, 4-methylcatechol, 4-t-butylcatechol, 2-methylresorcinol, 4-methylresorcinol and 2,3-dihydroxyacetophenone.

[0081] Examples of aminophenols include o-aminophenol, m-aminophenol, p-aminophenol, 2-(N,N-dimethylamino)phenol, and 4-(ethylamino)phenol.

[0082] Examples of nitrophenol include o-nitrophenol, m-nitrophenol, p-nitrophenol and 2,4-dinitrophenol.

[0083] Examples of nitrosophenol include o-nitrosophenol, m-nitrosophenol, p-nitrosophenol and α-nitroso-e-naphthol.

[0084] Examples of alkoxyphenols include 2-methoxyphenol, 2-ethoxyphenol, 2-isopropoxyphenol, 2-t-butoxyphenol, 4-methoxyphenol, 4-ethoxyphenol, 4-propoxyphenol, 4-butoxyphenol, 4-t-butoxyphenol, 4-heptoxyphenol, hydroquinone monobenzyl ether, t-butyl-4-methoxyphenol, di-t-butyl-4-methoxyphenol, pyrogallol1,2-dimethylether and hydroquinone monobenzoate.

[0085] Examples of tocopherol include α-tocopherol and 2,3-dihydro-2,2-dimethyl-7-hydroxybenzofuran. Petition 870230094863, dated 10 / 26 / 2023, page 27 / 91 21 / 58

[0086] Examples of polymerization inhibitors that are quinone compounds include p-benzoquinone, chloro-p-benzoquinone, 2,5-dichloro-p-benzoquinone, 2,6-dichloro-p-benzoquinone, tetrachloro-p-benzoquinone, tetrabromo-p-benzoquinone, 2,3-dimethyl-p-benzoquinone, 2,5-dimethyl-p-benzoquinone, methoxy-p-benzoquinone, and methyl-p-benzoquinone.

[0087] Examples of polymerization inhibitors that are nitrobenzene compounds include nitrobenzene, o-dinitrobenzene, m-dinitrobenzene, p-dinitrobenzene, 2,4-dinitrotoluene, dinitrodurene, and 2,2-diphenyl-1-picrylhydrazyl.

[0088] Examples of polymerization inhibitors which are compounds N-oxyl groups include 4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl, 4-oxo-2,2,6,6-tetramethylpiperidine-N-oxyl, 4-acetoxy-2,2,6,6-tetramethylpiperidine-N-oxyl, 2,2,6,6-tetramethylpiperidine-N-oxyl, piperidine-1-oxyl, 4-(dimethylamino)-2,2,6,6-tetramethylpiperidine-N-oxyl, 4-amino-2,2,6,6-tetramethylpiperidine-N-oxyl, 4-ethanoloxy-2,2,6,6-tetramethylpiperidine-N-oxyl, 4-benzoyloxy-2,2,6,6-tetramethylpiperidine-N-oxyl, 2,2,5,5-tetramethyl-piperidine-N-oxyl, 3-amino-2,2,5,5-tetramethyl-piperidine-N-oxyl, 4,4',4''-tris(2,2,6,6-tetramethyl-piperidine-N-oxyl)phosphite, 3-oxo-2,2,5,5-tetramethylpyrrolidine-N-oxyl, pyrrolidine-1-oxyl, 2,2,5,5-tetramethyl-1-oxa-3azacyclopentyl-3-oxy, 2,2,5,5-tetramethyl-3-pyrrolinyl-1-oxy-3-carboxylic acid, 2,2,3,3,5,5,6,6-octamethyl-1,4-diazacyclohexyl-1,4-diox, di-tert-butylnitroxide and di-tert-amylnitroxide.

[0089] Examples of polymerization inhibitors that are amine compounds include N,N-diphenylamine, alkylated diphenylamine, 4,4'-dicumyldiphenylamine, 4,4'-dioctyldiphenylamine, 4-aminodiphenylamine, p-nitrosodiphenylamine, N-nitrosodinaphthylamine, N-nitrosodiphenylamine, N-nitrosophenylnaphthylamine, N-nitrosophenylhydroxylamine, N,N'-dialkyl-p-phenylenediamine (the alkyl groups may be the same or different and may each independently comprise from 1 to 4 carbon atoms and may be linear or branched), N,N'-diphenyl-p-phenylenediamine, N-phenyl-N' Petition 870230094863, dated 10 / 26 / 2023, page 28 / 91 22 / 58 isopropyl-p-phenylenediamine, N-(1,3-dimethylbutyl)-N'-phenyl-1,4-phenylenediamine, N,N'-di-2-naphthyl-p-phenylenediamine, N,N-diethylhydroxylamine, 1,4benzenediamine, N-(1,4-dimethylpentyl)-N'-phenyl-1,4-benzenediamine, N(1,3-dimethylbutyl)-N'-phenyl-1,4-benzenediamine, 6-ethoxy-2,2,4-trimethyl-1,2dihydroquinoline, 2,2,4-trimethyl-1,2-dihydroquinoline polymer, aldolα-naphthylamine, N-phenyl-e-naphthylamine, 4-hydroxy-2,2,6,6-tetramethylpiperidine, 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, 1,4-di-hydroxy-2,2,6,6-tetramethylpiperidine and 1 -hydroxy-4-benzoyloxy-2,2,6,6-tetramethylpiperidine.

[0090] Examples of polymerization inhibitors that are phosphorus-containing compounds include triphenylphosphine, triphenyl phosphite, triethyl phosphite, tris(isodecyl) phosphite, tris(tridecyl) phosphite, phenyl diisooctyl phosphite, phenyl diisodecyl phosphite, phenyl di(tridecyl) phosphite, diphenyl isooctyl phosphite, diphenyl isodecyl phosphite, diphenyl tridecyl phosphite, phosphonic acid [1,1-diphenyl-4,4'-diylbistetrakis-2,4-bis(1,1-dimethylethyl)phenyl] ester, triphenyl phosphite, tris(nonylphenyl) phosphite, 4,4'-isopropylidenediphenol alkyl phosphite, tris(2,4-di-tert-butylphenyl) phosphite, tris(biphenyl) phosphite, distearyl pentaerythritol diphosphite, di(2,4-di-tert-butylphenyl) pentaerythritol diphosphate, di(nonylphenyl) pentaerythritol diphosphite, phenyl bisphenol-A pentaerythritol diphosphite, tetra(tridecyl)-4,4'-butylidenebis(3-methyl-6tert-butylphenol)diphosphite, hexa(tridecyl)-1,1,3-tris(2-methyl-4-hydroxy-5-tertbutylphenyl) butanetriphosphite, 3,5-di-tert-butyl-4-hydroxybenzyl phosphate diethyl ester,bis(4-tert-butylphenyl) sodium phosphate, sodium-2,2'-methylenebis(4,6-di-tert-butylphenyl) phosphate and 1,3-bis(diphenoxyphosphonyloxy)benzene.

[0091] Examples of polymerization inhibitors that are sulfur-containing compounds include diphenyl sulfide, phenothiazine, 3-oxophenothiazine, 5-oxophenothiazine, phenothiazine dimer, 1,4-dimercaptobenzene, 1,2-dimercaptobenzene, 2-mercaptophenol, 4-mercaptophenol, 2-(methylthio)phenol, 3,7-bis(dimethylamino)phenothiazinium chloride and sulfur (simple substance).

[0092] Examples of polymerization inhibitors that are iron-containing compounds include iron(III) chloride. Petition 870230094863, dated 10 / 26 / 2023, page 29 / 91 23 / 58

[0093] Examples of polymerization inhibitors that are copper-containing compounds include copper dimethyldithiocarbamate, copper diethyldithiocarbamate, copper dibutyldithiocarbamate, copper salicylate, copper acetate, copper thiocyanate, copper nitrate, copper chloride, copper carbonate, copper hydroxide, copper acrylate, and copper methacrylate.

[0094] Examples of a polymerization inhibitor that is a manganese-containing compound include manganese dialkyl dithiocarbamate (the alkyl groups are each one of a methyl group, an ethyl group, a propyl group, and a butyl group and may be the same or different), manganese diphenyl dithiocarbamate, manganese formate, manganese acetate, manganese octanoate, manganese naphthenate, manganese permanganate, and manganese salt of ethylenediaminetetraacetic acid.

[0095] Among those described above, component B is preferably at least one polymerization inhibitor(s) selected from the group consisting of a phenol compound, a Noxyl compound, an amine compound, a phosphorus-containing compound and a sulfur-containing compound, and more preferably at least one or more polymerization inhibitors selected from the group consisting of hydroquinone, 4-methoxyphenol, 2,4-dimethyl-6-t-butylphenol, 2,6-di-t-butyl4-methylphenol, 4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl, N,N-diphenylamine, N-nitrosodiphenylamine, triphenyl phosphite and phenothiazine, from the point of view of the quality stability of the composition containing methyl methacrylate during storage.

[0096] One or two or more component(s) B may be contained.

[0097] In cases where the composition containing methyl methacrylate comprises a compound that corresponds to both components A1 and B, the compound is considered to be component B. Thus, the composition containing methyl methacrylate must comprise component A1 different from the compound. In cases where two or more Petition 870230094863, dated 10 / 26 / 2023, page 30 / 91 24 / 58 compounds corresponding to both components A1 and B are contained, the compound with the highest molar concentration in the methyl methacrylate composition is considered as component B, and the other compound(s) is / are considered as component(s) A1. Concentrations of Component A1 and Component B

[0098] When the concentration of component A1 is MA1 (μmol / L) and the concentration of component B is MB (μmol / L), MB / MA1 is preferably 0.1 or more from the point of view of efficiency in reducing methylpyruvate production. The upper limit of MB / MA1 is not particularly restricted and is generally 100 or less.

[0099] MA1 is preferably from 1 to 85,000 μmol / L. When MA1 is 1 μmol / L or more, the effect of reducing the production of methyl methacrylate and methyl pyruvate dimer can be sufficiently achieved. When MA1 is 85,000 pmol / L or less, the impurity content after the production of the methyl methacrylate polymer by polymerization of the composition containing methyl methacrylate, according to the present invention, is reduced, so that adverse effects on the physical properties of the polymer can be avoided. The lower limit of MA1 is more preferably 10 μmol / L or more, and even more preferably 50 pmol / L or more. The upper limit of MA1 is most preferably 40,000 pmol / L or less, even more preferably 20,000 pmol / L or less, and particularly preferably 15,000 pmol / L or less.

[00100] MB is preferably from 1 to 7,000 pmol / L. When MB is 1 pmol / L or more, the effect of reducing the production of methyl methacrylate and methyl pyruvate dimer can be sufficiently obtained. When MB is 7,000 pmol / L or less, the impurity content after the production of the methyl methacrylate polymer by polymerization of the composition containing methyl methacrylate, according to the present Petition 870230094863, dated 10 / 26 / 2023, page 31 / 91 25 / 58 invention is reduced so that adverse effects on the physical properties of the polymer can be avoided. The lower limit of MB is more preferably 10 μmol / L or more, and even more preferably 40 pmol / L or more. The upper limit of MB is more preferably 5,000 pmol / L or less, and even more preferably 1,000 pmol / L or less. Methyl Methacrylate Concentration

[00101] The concentration of methyl methacrylate in the composition containing methyl methacrylate in the first aspect according to the present invention is from 99 to 99.99% by mass. When the concentration of methyl methacrylate is 99% by mass or more, the impurity content after the production of the methyl methacrylate polymer by polymerization of the composition containing methyl methacrylate is reduced, so that adverse effects on the physical properties of the polymer can be avoided. When the concentration of methyl methacrylate is 99.99% by mass or less, the purification cost can be reduced. The lower limit of the methyl methacrylate concentration is preferably 99.8% by mass or more. Component C

[00102] The composition containing methyl methacrylate in the first aspect according to the present invention may contain another compound (component C) provided that the composition satisfies a methyl methacrylate concentration of 99 to 99.99% by mass. Examples of component C include impurities produced during the production of methyl methacrylate. For example, methyl methacrylate may contain diacetyl as an impurity. From the point of view of reducing the color of the composition containing methyl methacrylate, the concentration of diacetyl is preferably 55 pmol / L or less, more preferably 20 pmol / L or less, even more preferably 10 pmol / L or less, and particularly preferably 1 pmol / L. Petition 870230094863, dated 10 / 26 / 2023, page 32 / 91 26 / 58 Analysis of the composition containing methyl methacrylate

[00103] The inclusion of component A1, component B, component C, and water by the composition containing methyl methacrylate can be determined, for example, by GC-MS measurement. When the GC-MS plot of the composition containing methyl methacrylate has a peak at the same retention time as a reference material for component A1, and when the m / z value detected in the mass spectrum of the peak corresponds to the exact mass of component A1, it can be determined that the composition containing methyl methacrylate contains component A1. In cases where the reference material for component A1 is not available, it can be determined that the peak is the peak of component A1 when the peak pattern of the mass spectrum shown in the GC-MS plot of the composition containing methyl methacrylate corresponds to the standard spectral mass of component A1 recorded in the mass spectrum database.In other words, it can be determined that the composition containing methyl methacrylate comprises component A1. Examples of mass spectrum databases include NIST20, NIST17, NIST14, and NIST14s. When detection by GC-MS measurement is impossible due to low volatility, LC-MS can be used for detection. The inclusion of a component B, a component C, and water can also be determined by the same method.

[00104] The concentration of methyl methacrylate can be determined, for example, by performing GC-FID measurement of the composition containing methyl methacrylate, quantifying methyl methacrylate using the area normalization method, and correcting the resulting value using the water concentration determined with a Karl-Fisher moisture meter. The concentration of component A1 can be determined, for example, by performing GC measurement of the composition containing methyl methacrylate and using the internal standard method. When Petition 870230094863, dated 10 / 26 / 2023, page 33 / 91 27 / 58 If the reference material for component A1 is not available and therefore cannot be quantified by the internal standard method, GC-FID measurement for any organic compound with a known concentration is performed under the same conditions as the composition containing methyl methacrylate, and then the concentration of component A1 can be calculated using the following equation: Concentration of component A1 (pmol / L) =^- xx M

[00105] In the equation, N is the number of carbon atoms that an organic compound with known concentration contains in a molecule; Nai is the number of carbon atoms that component A1 contains in a molecule; S A1 is the peak area of ​​component A1, S is the peak area of ​​an organic compound with known concentration, and M is the concentration (pmol / L) of an organic component with known concentration.

[00106] When quantification by GC measurement is impossible due to low volatility, a chromatography method such as LC can be used for quantification.

[00107] The concentrations of component B and component C can also be determined by the same method as component A1 described above.

[00108] The inclusion of water by the composition containing methyl methacrylate and its concentration can be determined by the Karl-Fischer method. Composition 2 containing Methyl Methacrylate

[00109] A composition containing methyl methacrylate in a second aspect according to the present invention comprises methyl methacrylate and an α,β-unsaturated carboxylate ester represented by the following Formula (2) (component A2), wherein the concentration of methyl methacrylate is from 99 to 99.99% by mass. When the concentration of component A2 is MA2 (pmol / L), MA2 is from 1 to 40,000 pmol / L. Petition 870230094863, dated 10 / 26 / 2023, page 34 / 91 28 / 58

[00110] In Formula (2) above, R5, R6 and R7 each independently represent a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, a hydroxy group, an alkoxy group, an amino group, a monovalent group containing a carbonyl group, an alkylthio group or an arylthio group. R8 represents an alkyl group, an alkenyl group or an aryl group. R5 and R6, R6 and R7, and R7 and R8 may be linked together to form a ring, except when R5= H, R6= H, R7= CH3 and R8= CH3, that is, when the α,β-unsaturated carbonyl compound represented by Formula (2) is methyl methacrylate. H represents a hydrogen atom, C represents a carbon atom and O represents an oxygen atom.

[00111] The composition containing methyl methacrylate may also contain component B, component C, or water, provided that the composition satisfies a methyl methacrylate concentration of 99 to 99.99% by mass. Each item will be described in detail. Component A2

[00112] The methyl methacrylate-containing composition in the second aspect according to the present invention comprises an α,β-unsaturated carboxylate ester represented by Formula (2) described above (component A2). When the methyl methacrylate-containing composition comprises a component A2, because component A2 as a single molecule can absorb a high amount of ultraviolet light, the production of hydroxyl radicals can be sufficiently reduced. Thus, even in cases where a component B that retains the produced hydroxyl radicals is not present, the production of methyl methacrylate and methyl pyruvate dimers can be reduced. However, the methyl methacrylate-containing composition comprises Petition 870230094863, dated 10 / 26 / 2023, page 35 / 91 29 / 58 preferably a component B as described above from the point of view that the production of methyl methacrylate and methyl pyruvate dimers can be further reduced.

[00113] The molecular weight of component A2 is preferably 1,000 or less. When the molecular weight is 1,000 or less, the number of conjugated double bonds per unit mass can be increased, so that the effect of the present invention can be obtained with less weight. The molecular weight of component A2 is more preferably 800 or less, even more preferably 600 or less, and particularly preferably 400 or less.

[00114] In Formula (2) above, R5, R6 and R7 each independently represent a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, a hydroxy group, an alkoxy group, an amino group, a monovalent group containing a carbonyl group, an alkylthio group or an arylthio group. R8 in Formula (2) described above represents an alkyl group, an alkenyl group or an aryl group. R5, R6, R7 and R8 may be the same or different from each other.

[00115] When R5, R6, R7, and R8 satisfy the conditions described above, the conjugated pi system in component A2 is maintained, and thus component A2 has the property of absorbing a wide wavelength of ultraviolet light, so that the effect of the present invention can be obtained. R5, R6, and R7 are each preferably a hydrogen atom, a C1-5 alkyl group, a C2-5 alkenyl group, a C1-12 aryl group, a C1-6 alkoxy group, an amino group, a monovalent group containing a carbonyl group, or a C1-5 alkylthio group. They are highly stable substituents and therefore can prevent component A2 from being transformed into other compounds during storage. When component A2 has such a substituent, a quantity of ultraviolet light absorbed by component A2 as a single molecule will be sufficient. R5, R6, and R7 are more preferably a hydrogen atom Petition 870230094863, dated 10 / 26 / 2023, page 36 / 91 30 / 58 of hydrogen or a C1-5 alkyl group, and even more preferably a hydrogen atom, a methyl group, an ethyl group, an n-propyl group, or an isopropyl group. R8 is more preferably a C1-5 alkyl group, a C2-5 alkenyl group, or a C1-12 aryl group. These are highly stable substituents and therefore can prevent component A2 from being transformed into other compounds during storage. R8 is more preferably a C1-5 alkyl group, more preferably a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, or an isopentyl group, and particularly preferably a methyl group. When R8 is the structure described above, the composition containing methyl methacrylate can have greater quality stability during storage.

[00116] In preferred embodiments, the alkyl group, the alkenyl group, the aryl group, the hydroxy group, the alkoxy group, the amine group, the monovalent group containing a carbonyl group, the alkylthio group, the arylthio group and the like in Formula (2) described above are the same as Formula (1) described above.

[00117] R5 and R6, R6 and R7, and R7 and R8 can be linked together to form a ring. Examples of compounds in which R5 and R6 are linked to form a ring include 2-cyclohexylidenemethyl propionate and 2-cyclopentylidenemethyl propionate. Examples of compounds in which R6 and R7 are linked to form a ring include methyl 1-cyclohexene-1-carboxylate and methyl 1-cyclopentene-1-carboxylate. Examples of compounds in which R7 and R8 are linked to form a ring include α-methylene-δ-valerolactone and α-methylene-γ-butyrolactone.

[00118] Among the compounds that satisfy the conditions described above, component A2 is preferably methyl acrylate, butyl acrylate, ethyl methacrylate, methyl crotonate, cis-methyl crotonate, isobutyl methacrylate, butyl methacrylate, propyl methacrylate, isopentyl methacrylate, methyl 2-methylene-3-butenoate, 3,3 Petition 870230094863, dated 10 / 26 / 2023, page 37 / 91 31 / 58 methyl dimethylacrylate, methyl 2-ethylacrylate, methyl 2-pentenoate, methyl cinnamate, methyl 3-methoxyacrylate, dimethyl fumarate, methyl 2-cyclohexylidenepropionate, methyl 2-cyclopentylidenepropionate, methyl 1-cyclohexene-1-carboxylate, methyl 1-cyclopentene-1-carboxylate, α-methylene-δ-valerolactone or α-methylene-γ-butyrolactone, more preferably methyl acrylate, butyl acrylate, ethyl methacrylate, methyl crotonate, cis-methyl crotonate, isobutyl methacrylate, butyl methacrylate, propyl methacrylate, isopentyl methacrylate, methyl 2-methylene-3-butenoate, 3,3-dimethylacrylate, 2-ethylacrylate, 2-pentenoate, methyl cinnamate, 3-methoxyacrylate, dimethyl fumarate or 1-cyclohexene-1-methylcarboxylate, and even more preferably methyl acrylate,Ethyl methacrylate or methyl crotonate, from the point of view of the quality stability of the composition containing methyl methacrylate during storage.

[00119] One or two or more component(s) A2 may be contained in the composition containing methyl methacrylate in the second aspect according to the present invention. Component B

[00120] In preferred embodiments where the composition containing methyl methacrylate comprises a component B, component B is the same as the first aspect. One or two or more component(s) B may be contained.

[00121] In cases where the composition containing methyl methacrylate comprises a compound that corresponds to both components A2 and B, the compound is considered to be component A2. Thus, the case where the composition containing methyl methacrylate comprises component A2 and component B means that the composition comprises component B different from the compound. In cases where two or more compounds corresponding to both are contained Petition 870230094863, dated 10 / 26 / 2023, pp. 38 / 91 32 / 58 of components A2 and B, the compound with the highest molar concentration in the methyl methacrylate composition is considered to be component A2, and the other compound(s) is / are considered to be component(s) B. Concentrations of Component A2 and Component B

[00122] MB / MA2 is preferably 0.1 or more from the point of view of efficiency in reducing methyl pyruvate production. The upper limit of MB / MA2 is not particularly restricted and is generally 100 or less.

[00123] MA2 is from 1 to 40,000 pmol / L. When MA2 is 1 μmol / L or more, the effect of reducing the production of methyl methacrylate and methyl pyruvate dimer can be sufficiently obtained. When MA2 is 40,000 pmol / L or less, the impurity content after the production of the methyl methacrylate polymer by polymerization of the composition containing methyl methacrylate, according to the present invention, is reduced, so that adverse effects on the physical properties of the polymer can be avoided. The lower limit of MA2 is more preferably 10 μmol / L or more, and even more preferably 50 μmol / L or more. The upper limit of MA2 is more preferably 10,000 pmol / L or less, even more preferably 5,000 pmol / L or less, and most preferably 500 pmol / L or less.

[00124] MB's preferred modes are the same as those in the first aspect. Methyl Methacrylate Concentration

[00125] In preferred embodiments, the concentration of methyl methacrylate is the same as in the first aspect. Component C

[00126] In preferred modalities, component C is equal to the first aspect. Petition 870230094863, dated 10 / 26 / 2023, pp. 39 / 91 33 / 58 Analysis of the composition containing methyl methacrylate

[00127] The method for confirming that the composition containing methyl methacrylate contains a component A2, a component B, a component C and water, and the method for measuring the concentrations of methyl methacrylate, a component A2, a component B, a component C, and water are the same as in the first aspect. Composition 3 containing Methyl Methacrylate

[00128] A composition containing methyl methacrylate in a third aspect according to the present invention comprises methyl methacrylate and at least one compound(s) (component A3) selected from the group consisting of methyl acrylate, butyl acrylate, ethyl methacrylate, methyl crotonate, methyl cis-crotonate, isobutyl methacrylate, butyl methacrylate, propyl methacrylate, isopentyl methacrylate, methyl 2-methylene-3-butenoate, methyl 3,3-dimethylacrylate, methyl 2-ethylacrylate, methyl 2-pentenoate, methyl cinnamate, methyl 3-methoxyacrylate, dimethyl fumarate, methyl 1-cyclohexene-1-carboxylate, methacrylamide, acrylic acid, crotonic acid, cis-crotonic acid, acid 3,3-dimethylacrylic acid, 2-ethylacrylic acid, 2-methylene-3-butenoic acid and trans-3-hexen-2-one, wherein the concentration of methyl methacrylate is 99 to 99.99% by mass. When the concentration of component A3 is MA3 (μmol / L), MA3 is 1 to 40,000 μmol / L.

[00129] The composition containing methyl methacrylate may also contain component B, component C, or water, provided that the composition satisfies a methyl methacrylate concentration of 99 to 99.99% by mass. Each item will be described in detail. Component A3

[00130] The composition containing methyl methacrylate in the third aspect according to the present invention comprises at least one compound(s) (component A3) selected from the group that Petition 870230094863, dated 10 / 26 / 2023, pp. 40 / 91 34 / 58 consists of methyl acrylate, butyl acrylate, ethyl methacrylate, methyl crotonate, cis-methyl crotonate, isobutyl methacrylate, butyl methacrylate, propyl methacrylate, isopentyl methacrylate, methyl 2-methylene-3-butenoate, methyl 3,3-dimethylacrylate, methyl 2-ethylacrylate, methyl 2-pentenoate, methyl cinnamate, methyl 3-methoxyacrylate, dimethyl fumarate, methyl 1-cyclohexene-1-carboxylate, methacrylamide, acrylic acid, crotonic acid, cis-crotonic acid, 3,3-dimethylacrylic acid, 2-ethylacrylic acid, 2-methylene-3-butenoic acid and trans-3-hexen-2-one. When the composition containing methyl methacrylate comprises an A3 component, the A3 component as a single molecule can absorb a high amount of ultraviolet light, and the production of hydroxyl radicals can be sufficiently reduced.Thus, even in cases where a component B that retains the produced hydroxyl radicals is not present, the production of methyl methacrylate and methyl pyruvate dimers can be reduced. However, the composition containing methyl methacrylate preferably comprises component B as described above, from the point of view that the production of methyl methacrylate and methyl pyruvate dimers can be further reduced.

[00131] The molecular weight of component A3 is preferably 200 or less. When the molecular weight is 200 or less, the number of conjugated double bonds per unit mass can be increased, so that the effect of the present invention can be obtained with less weight. The molecular weight of component A3 is more preferably 150 or less, even more preferably 130 or less, and particularly preferably 110 or less.

[00132] Component A3 is preferably at least one selected from the group consisting of methyl acrylate, methyl crotonate, acrylic acid and crotonic acid.

[00133] One or two or more A3 component(s) may be contained Petition 870230094863, dated 10 / 26 / 2023, pp. 41 / 91 35 / 58 in the composition containing methyl methacrylate in the third aspect according to the present invention. Component B

[00134] In preferred embodiments where the composition containing methyl methacrylate comprises a component B, component B is the same as the first aspect. One or two or more component(s) B may be contained.

[00135] In cases where the composition containing methyl methacrylate comprises a compound that corresponds to both components A3 and B, the compound is considered to be component A3. Thus, the case where the composition containing methyl methacrylate comprises component A3 and component B means that the composition comprises component B different from the compound. In cases where two or more compounds corresponding to both components A3 and B are contained, the compound with the highest molar concentration in the methyl methacrylate composition is considered to be component A3, and the other compound(s) is / are considered to be component B. Concentrations of Component A3 and Component B

[00136] MB / MA3 is preferably 0.1 or more from the point of view of efficiency in reducing methyl pyruvate production. The upper limit of MB / MA3 is not particularly restricted and is generally 100 or less.

[00137] MA3 is from 1 to 40,000 pmol / L. When MA3 is 1 μmol / L or more, the effect of reducing the production of methyl methacrylate and methyl pyruvate dimer can be sufficiently obtained. When MA2 is 40,000 pmol / L or less, the impurity content after the production of the methyl methacrylate polymer by polymerization of the composition containing methyl methacrylate, according to the present invention, is reduced, so that adverse effects on the physical properties of the Petition 870230094863, dated 10 / 26 / 2023, p. 42 / 91 36 / 58 polymer can be avoided. The lower limit of MA3 is more preferably 10 μmol / L or more, and even more preferably 50 μmol / L or more. The upper limit of MA3 is more preferably 10,000 pmol / L or less, even more preferably 5,000 pmol / L or less, and most preferably 500 μmol / L or less.

[00138] MB's preferred modes are the same as in the first aspect. Methyl Methacrylate Concentration

[00139] The preferred modalities of methyl methacrylate concentration are the same as in the first aspect. Component C

[00140] The preferred modes of component C are the same as those of the first aspect. Analysis of the composition containing methyl methacrylate

[00141] The method for confirming that the composition containing methyl methacrylate contains a component A3, a component B, a component C and water, and the method for measuring the concentrations of methyl methacrylate, a component A3, a component B, a component C, and water are the same as in the first aspect. Method for producing a composition containing methyl methacrylate

[00142] The method for producing the composition containing methyl methacrylate, according to the present invention, may be a method in which a component A1, a component A2 or a component A3 (hereinafter correctly referred to as component A) and a component B are added to methyl methacrylate. The methyl methacrylate to be used may be a commercially available product, or methyl methacrylate produced by known methods, such as the acetone cyanohydrin (ACH) method, the novel acetone cyanohydrin (novel ACH) method, the C4 direct oxidation method, the direct methyl esterification method, the ethylene method and the novel ethylene method. Petition 870230094863, dated 10 / 26 / 2023, pp. 43 / 91 37 / 58 can be used. Component A and component B to be used may be commercially available products or may be those synthesized by known methods. When methyl methacrylate produced by a known method, such as the acetone cyanohydrin (ACH) method, the novel acetone cyanohydrin (new ACH) method, the C4 direct oxidation method, the direct methyl esterification method, the ethylene method, or the novel ethylene method, is used, component A or component B may be added to the raw materials or during the production process to produce the composition containing methyl methacrylate. In cases where component A or component B is produced as a byproduct during the methyl methacrylate production process, a portion of the component A or component B produced may be left over for the production of the composition containing methyl methacrylate. Methods for evaluating storage stability and thermal stability.

[00143] The composition containing methyl methacrylate, according to the present invention, possesses high-quality stability during storage. The method for evaluating the quality stability of the composition containing methyl methacrylate during storage can be, for example, a method in which the composition containing methyl methacrylate is actually stored for a long period, and the quantities of methyl methacrylate and methyl pyruvate dimers produced are determined. From the point of view of simplicity of work, a method can be carried out in which the composition containing methyl methacrylate is heated for a short period of time, and the quantities of methyl methacrylate and methyl pyruvate dimers produced are determined. In cases of heating for a short period of time, the heating temperature is preferably from 50 to 100°C, and the heating time period is Petition 870230094863, dated 10 / 26 / 2023, pp. 44 / 91 38 / 58 preferably from 1 to 24 hours. In the present invention, the quality stability of the composition containing methyl methacrylate during storage is evaluated based on the amounts of methyl methacrylate and methyl pyruvate dimers produced when the composition containing methyl methacrylate is stored at 25°C for 14 days.

[00144] Methyl methacrylate polymer production method

[00145] The methyl methacrylate polymer production method according to the present invention comprises a polymerization step of a polymeric composition comprising the methyl methacrylate-containing composition according to the present invention. Polymer Composition

[00146] The polymeric composition may comprise, as required, a monomer that can be copolymerized with methyl methacrylate and other additives. Monomer that can be copolymerized with methyl methacrylate

[00147] Examples of monomers that can be copolymerized with methyl methacrylate include the following: a methacrylate ester, such as ethyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, tert-butyl methacrylate, 2-ethylhexyl methacrylate, phenyl methacrylate or benzyl methacrylate; an acrylate ester, such as methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, tert-butyl acrylate or 2-ethylhexyl acrylate; an unsaturated carboxylic acid, such as acrylic acid, methacrylic acid, maleic acid, or itaconic acid; an unsaturated carboxylic anhydride, such as maleic anhydride or itaconic anhydride; maleimide, such as N-phenylmaleimide or N-cyclohexylmaleimide; Petition 870230094863, dated 10 / 26 / 2023, pp. 45 / 91 39 / 58 a vinyl monomer containing a hydroxy group, such as 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate or 2-hydroxypropyl methacrylate; a vinyl ester, such as vinyl acetate or vinyl benzoate; vinyl chloride, vinylidene chloride and their derivatives; a nitrogen-containing vinyl monomer, such as methacrylamide or acrylonitrile; a monomer containing an epoxy group, such as glycidyl acrylate or glycidyl methacrylate; an aromatic vinyl monomer, such as styrene or alpha-methylstyrene; alkane diol di(meth)acrylate, such as ethylene glycol di(meth)acrylate, 1,2-propylene glycol di(meth)acrylate, 1,3butylene glycol di(meth)acrylate or 1,6-hexanediol di(meth)acrylate)acrylate; polyoxyalkylene glycol di(meth) acrylate, such as diethylene glycol di(meth) acrylate, dipropylene glycol di(meth) acrylate, triethylene glycol (meth) acrylate, tetraethylene glycol di(meth) acrylate, polyethylene glycol di(meth) acrylate, or neopentyl glycol di(meth) acrylate; A vinyl monomer possessing two or more unsaturated ethylenic bonds in its molecule, such as divinylbenzene; an unsaturated polyester prepolymer obtained from at least one polyvalent carboxylic acid including ethylene unsaturated polycarboxylic acid and at least one diol; and a vinyl ester prepolymer obtained by acrylic modification of one end of an epoxy group.

[00148] Among those described above, the monomer that can be copolymerized with methyl methacrylate is preferably at least one selected from the group consisting of methacrylate esters and acrylate esters. This allows polymerization of the composition Petition 870230094863, dated 10 / 26 / 2023, pp. 46 / 91 40 / 58 polymeric to obtain a methyl methacrylate polymer with an excellent balance between transparency, heat resistance and moldability. The monomer that can be copolymerized with methyl methacrylate is most preferably an acrylate ester and, particularly preferably, at least one selected from the group consisting of methyl acrylate, ethyl acrylate and n-butyl acrylate.

[00149] One or two or more monomer(s) that can be copolymerized with methyl methacrylate may be used. When component A is a monomer that can be copolymerized with methyl methacrylate, component A may be used as a monomer that can be copolymerized with methyl methacrylate, or a monomer that can be copolymerized with methyl methacrylate in addition to component A may be used.

[00150] The lower limit of the amount of monomer that can be copolymerized with methyl methacrylate contained in the polymer composition is preferably 0.01 parts by mass or more relative to 100 parts by mass of methyl methacrylate. This allows obtaining a methyl methacrylate polymer with high transparency. The upper limit of the amount of monomer that can be copolymerized with methyl methacrylate relative to 100 parts by mass of methyl methacrylate is preferably 50 parts by mass or less, more preferably 40 parts by mass or less, and even more preferably 30 parts by mass or less. The lower limit of the amount of monomer that can be copolymerized with methyl methacrylate relative to 100 parts by mass of methyl methacrylate is more preferably 0.1 part by mass or more, and even more preferably one part by mass or more. Other additives

[00151] Other additives preferably include a polymerization initiator. Other additives may also include, for example, a Petition 870230094863, dated 10 / 26 / 2023, pp. 47 / 91 41 / 58 chain transfer agent, a mold release agent, a lubricant, a plasticizer, an antioxidant, an antistatic agent, a light stabilizer, an ultraviolet absorber, a flame retardant, a flame retardant promoter, a polymerization inhibitor, a filler, a pigment, a dye, a silane coupling agent, a leveling agent, an antifoaming agent and a fluorescent agent, as required. One or two or more other additives may be contained.

[00152] Examples of polymerization initiators include the following:

[00153] an azo compound, such as 2,2'-azobisisobutyronitrile, 2,2'-azobis(2-methylbutyronitrile), 2,2'-azobis(2-methylpropionitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), 2,2'-azobis(2,4,4-trimethylpentane), 2-2'-azobis(2-methylpropane), 1,1-azobis(cyclohexanecarbonitrile) and dimethyl-2,2'-azobisisobutyrate; an organic peroxide, such as benzoyl peroxide, 2,5-dimethyl-2,5-bis(t-butylperoxy)hexane, 1,1-bis(t-butylperoxy)cyclohexane, 1,1-bis(t-butylperoxy)-3,5,5-trimethylcyclohexane, t-butylperoxy-2-ethylhexanoate, t-butylperoxyisobutyrate, t-butylperoxybenzoate, t-hexylperoxybenzoate, t-butylperoxyisopropyl monocarbonate, t-butylperoxy-3,5,5-trimethylhexanoate, t-butyl peroxylaurate, t-butyl peroxyacetate, t-hexylperoxyisopropyl monocarbonate, t-hexylperoxy-2-ethylhexanoate, t-amylperoxy-2-ethylhexanoate, 1,1,3,3-tetramethylbutylperoxyethylhexanoate, 1,1,2-trimethylpropylperoxy-2-ethylhexanoate, 1,1,3,3-tetramethylbutylperoxyisopropyl monocarbonate, 1,1,2-trimethyl propyl peroxyisopropyl monocarbonate, 1,1,3,3-tetramethyl butyl peroxyisononanoate, 1,1,2-trimethyl propyl peroxyisononanoate, di-t-butyl peroxide, di-t-hexyl peroxide, lauroyl peroxide and dilauroyl peroxide; a persulfate compound, such as potassium persulfate; and a redox polymerization initiator.

[00154] Among those described above, the polymerization initiator Petition 870230094863, dated 10 / 26 / 2023, pp. 48 / 91 42 / 58 is preferably at least one selected from the group consisting of the azo compound and the organic peroxide from the point of view of storage stability and reactivity with methyl methacrylate.

[00155] The amount of polymerization initiator used is preferably from 0.0001 to one part by mass in relation to 100 parts by mass of the total methyl methacrylate and monomer that can be copolymerized with methyl methacrylate. Polymerization Method of Polymer Composition

[00156] Examples of polymerization methods include a bulk polymerization method, a solution polymerization method, an emulsion polymerization method, and a suspension polymerization method. From the point of view of the environmental burden due to the use of solvents and the like, and the transparency of the methyl methacrylate polymer to be obtained, a bulk polymerization method is preferable.

[00157] Specific means for the bulk polymerization method are not particularly limited, and a known casting polymerization method, such as a cell casting method or a continuous casting method, can be used for production.

[00158] The casting polymerization method is a method for obtaining methyl methacrylate polymer by injecting a polymeric composition into a mold composed of two inorganic glass plates or metal plates (e.g., SUS plates) placed face to face at a predetermined distance with the periphery sealed with a gasket, like a soft resin tube, and allowing the polymerization of the composition.

[00159] The mold for cellular casting polymerization is not particularly limited and known molds can be used. Examples of molds for cellular casting include those in which two bodies Petition 870230094863, dated 10 / 26 / 2023, pp. 49 / 91 43 / 58 similar to plates, such as inorganic glass plates, chrome-plated metal plates, and stainless steel plates, are placed opposite each other at a predetermined distance, and a gasket is placed around the periphery to allow the plate-shaped bodies and the joint to form a sealed space. Examples of molds for continuous casting include those in which a sealed space is formed by opposite faces of a pair of endless belts running in the same direction and at the same speed, and joints running at the same speed as the endless belt on both sides of the mold.

[00160] The void spacing in a mold is adjusted as appropriate to obtain a resin sheet with a desired thickness and is generally 1 to 30 mm.

[00161] The polymerization temperature is preferably from 125 to 210°C. This allows for achieving an appropriate polymerization rate. More preferably, the lower limit of the polymerization temperature is 130°C or higher, and the upper limit is 180°C or lower. The polymerization time is not particularly limited and can be, for example, from 0.5 to 24 hours. EXAMPLES

[00162] The present invention will be described in detail with reference to the Examples and Comparative Examples below, but is not limited to these Examples. Unless otherwise indicated, the terms % and ppm in the examples and comparative examples mean % by weight and ppm by weight, respectively.

[00163] The concentration of water contained in a methyl methacrylate reagent was determined by the Karl-Fischer method. The composition of the components of the methyl methacrylate-containing composition before storage was determined based on the amounts of raw materials added. Methyl methacrylate and methyl pyruvate dimers in the methyl methacrylate-containing composition after Petition 870230094863, dated 10 / 26 / 2023, pp. 50 / 91 The 44 / 58 values ​​to be stored were determined by an absolute calibration curve method using GC-MS. The measurement conditions for GC-MS are shown below.

[00164] Instrument: GC-MS measuring system (product name: QP-2010SE, manufactured by Shimadzu Corporation) Conditions for GC

[00165] Column (product name: DB-WAX, manufactured by Agilent Technologies, Inc.);

[00166] Length: 60 m, Inner diameter: 0.32 mm, Film thickness: 1.00 μm;

[00167] Injection volume: 1.0 pL;

[00168] Vaporization chamber temperature: 210°C;

[00169] Column oven temperature: held at 35°C for 10 minutes, raised from 35°C to 150°C at 5°C / min, held at 150°C for 17 minutes, raised from 150°C to 220°C at 5°C / min, and held at 220°C for 6 minutes;

[00170] Carrier gas: helium;

[00171] Injection mode: split (split ratio: 50);

[00172] Control mode: constant linear speed (25.0 cm / sec);

[00173] Pressure: 26.1 kPa;

[00174] Total flow rate: 52.5 mL / min;

[00175] Purge flow rate: 3.0 mL / min; and

[00176] Column flow rate: 0.97 mL / min.

[00177] Conditions for EM

[00178] Ionization method: EI (electronic ionization);

[00179] Ion source temperature: 250°C;

[00180] Interface temperature: 250°C;

[00181] detection range m / z: 10 to 300; and

[00182] Detection time: 70 minutes.

[00183] Determination of water concentration by the Karl method Petition 870230094863, dated 10 / 26 / 2023, page 51 / 91 45 / 58 Fischer's analysis was carried out using automated water measurement equipment (product name: AQV-2200, manufactured by Hiranuma Co., Ltd.). Example 1

[00184] Using methyl acrylate as component A, 0.0186 g of component A were added to 10.0701 g of a methyl methacrylate reagent (water concentration: 240 ppm) to prepare a methyl methacrylate solution (solution A-1). The concentration of component A in solution A-1 is shown in Table 1.

[00185] Using 2,4-dimethyl-6-t-butylphenol as component B, 0.0228 g of component B were added to 10.0026 g of a methyl methacrylate reagent (water concentration: 240 ppm) to prepare a methyl methacrylate solution (B-1 solution). The concentration of component B in solution B-1 is shown in Table 1.

[00186] Next, 0.1072 g of solution A-1 and 0.1062 g of solution B-1 were added to 20.0348 g of a methyl methacrylate reagent (water concentration: 240 ppm) to prepare a composition containing methyl methacrylate. The concentrations of the components in the composition containing methyl methacrylate are shown in Table 2. The concentration of component A in the composition containing methyl methacrylate is defined as MA (μmol / L).

[00187] The composition containing methyl methacrylate was stored at 25°C for 14 days. The amounts of methyl methacrylate and methyl pyruvate dimers produced in the composition containing methyl methacrylate after storage are shown in Table 2. Examples 2 to 9

[00188] Solutions A-1 were prepared in the same manner as in Example 1, except that a compound shown in Table 1 was used as component A, and the amounts of the reagent methyl methacrylate were different. Petition 870230094863, dated 10 / 26 / 2023, pp. 52 / 91 46 / 58 and component A were modified as shown in Table 1.

[00189] Solutions B-1 were prepared in the same way as in Example 1.

[00190] Next, the compositions containing methyl methacrylate were prepared in the same manner as in Example 1, except that the amounts of the methyl methacrylate reagent, solution A-1 and solution B-1 were altered as shown in Table 2. The concentrations of the components in the composition containing methyl methacrylate are shown in Table 2.

[00191] The methyl methacrylate-containing compositions obtained were stored as in Example 1. The amounts of methyl methacrylate and methyl pyruvate dimers produced in the methyl methacrylate-containing compositions after storage are shown in Table 2. Examples 10 and 15

[00192] Solutions A-1 were prepared in the same manner as in Example 1, except that a compound shown in Table 1 was used as component A, and the amounts of the methyl methacrylate reagent and component A were altered as shown in Table 1.

[00193] Solutions B-1 were prepared in the same manner as in Example 1, except that the quantities of the methyl methacrylate reagent and component B were altered as shown in Table 1.

[00194] Next, the compositions containing methyl methacrylate were prepared in the same manner as in Example 1, except that the amounts of the methyl methacrylate reagent, solution A-1 and solution B-1 were altered as shown in Table 2. The concentrations of the components in the compositions containing methyl methacrylate are shown in Table 2. Petition 870230094863, dated 10 / 26 / 2023, pp. 53 / 91 47 / 58

[00195] The methyl methacrylate-containing compositions obtained were stored as in Example 1. The amounts of methyl methacrylate and methyl pyruvate dimers produced in the methyl methacrylate-containing compositions after storage are shown in Table 2. Examples 16 to 22

[00196] Solutions A-1 were prepared in the same way as in Example 1.

[00197] Solutions B-1 were prepared in the same manner as in Example 1, except that a compound shown in Table 1 was used as component B, and the amounts of the methyl methacrylate reagent and component B were altered as shown in Table 1.

[00198] Next, the compositions containing methyl methacrylate were prepared in the same manner as in Example 1, except that the amounts of the methyl methacrylate reagent, solution A-1 and solution B-1 were altered as shown in Table 2. The concentrations of the components in the compositions containing methyl methacrylate are shown in Table 2.

[00199] The methyl methacrylate-containing compositions obtained were stored as in Example 1. The amounts of methyl methacrylate and methyl pyruvate dimers produced in the methyl methacrylate-containing compositions after storage are shown in Table 2. Example 23

[00200] A solution A-1 and a solution B-1 were prepared in the same way as in Example 1.

[00201] Next, a composition containing methyl methacrylate was prepared in the same manner as in Example 1, except that the quantities of the methyl methacrylate reagent, solution A-1 and the Petition 870230094863, dated 10 / 26 / 2023, pp. 54 / 91 48 / 58 solution B-1 were altered as shown in Table 2. The concentrations of the components in the composition containing methyl methacrylate are shown in Table 2.

[00202] The composition containing methyl methacrylate obtained was stored as in Example 1. The amounts of methyl methacrylate and methyl pyruvate dimers produced in the composition containing methyl methacrylate after storage are shown in Table 2. Example 24

[00203] A B-1 solution was prepared in the same way as in Example 1.

[00204] Next, using methyl acrylate as component A, 0.0205 g of component A and 0.1086 g of a B-1 solution were added to 20.0166 g of a methyl methacrylate reagent (water concentration: 240 ppm) to prepare a composition containing methyl methacrylate. The concentrations of the components in the composition containing methyl methacrylate are shown in Table 2.

[00205] The composition containing methyl methacrylate obtained was stored as in Example 1. The amounts of methyl methacrylate and methyl pyruvate dimers produced in the composition containing methyl methacrylate after storage are shown in Table 2. Example 25

[00206] A B-1 solution was prepared in the same manner as in Example 1, except that the quantities of the methyl methacrylate reagent and component B were altered as shown in Table 1.

[00207] Next, a composition containing methyl methacrylate was prepared in the same manner as in Example 24, except that the amounts of the reagent methyl methacrylate, component A, and Petition 870230094863, dated 10 / 26 / 2023, pp. 55 / 91 49 / 58 solution B-1 were altered as shown in Table 2. The concentrations of the components in the composition containing methyl methacrylate are shown in Table 2.

[00208] The composition containing methyl methacrylate obtained was stored as in Example 1. The amounts of methyl methacrylate and methyl pyruvate dimers produced in the composition containing methyl methacrylate after storage are shown in Table 2. Example 26

[00209] A solution A-1 and a solution B-1 were prepared in the same way as in Example 1.

[00210] Next, a composition containing methyl methacrylate was prepared in the same manner as in Example 1, except that the amounts of the methyl methacrylate reagent, solution A-1, and solution B-1 were altered as shown in Table 2. The concentrations of the components in the composition containing methyl methacrylate are shown in Table 2.

[00211] The composition containing methyl methacrylate obtained was stored as in Example 1. The amounts of methyl methacrylate and methyl pyruvate dimers produced in the composition containing methyl methacrylate after storage are shown in Table 2. Examples 27 and 28

[00212] Solutions A-1 were prepared in the same way as in Example 1.

[00213] Solutions B-1 were prepared in the same manner as in Example 1, except that the quantities of the methyl methacrylate reagent and component B were altered as shown in Table 1.

[00214] Next, compositions containing methyl methacrylate Petition 870230094863, dated 10 / 26 / 2023, pp. 56 / 91 50 / 58 were prepared in the same manner as in Example 1, except that the quantities of the methyl methacrylate reagent, solution A-1 and solution B-1 were altered as shown in Table 2. The concentrations of the components in the compositions containing methyl methacrylate are shown in Table 2.

[00215] The methyl methacrylate-containing compositions obtained were stored as in Example 1. The amounts of methyl methacrylate and methyl pyruvate dimers produced in the methyl methacrylate-containing compositions after storage are shown in Table 2. Example 29

[00216] A solution A-1 was prepared in the same way as in Example 1.

[00217] Next, 0.1048 g of solution A-1 were added to 20.0196 g of a methyl methacrylate reagent (water concentration: 240 ppm) to prepare a composition containing methyl methacrylate. The concentrations of the components in the composition containing methyl methacrylate are shown in Table 2.

[00218] The composition containing methyl methacrylate obtained was stored as in Example 1. The amounts of methyl methacrylate and methyl pyruvate dimers produced in the composition containing methyl methacrylate after storage are shown in Table 2. Comparative Example 1

[00219] A B-1 solution was prepared in the same way as in Example 1.

[00220] Next, 0.2213 g of solution B-1 were added to 40.0273 g of a methyl methacrylate reagent (water concentration: 240 ppm) to prepare a composition containing methyl methacrylate. The concentrations of the components in the composition containing methyl methacrylate are shown in Table 2. Petition 870230094863, dated 10 / 26 / 2023, pp. 57 / 91 51 / 58

[00221] The composition containing methyl methacrylate obtained was stored as in Example 1. The amounts of methyl methacrylate and methyl pyruvate dimers produced in the composition containing methyl methacrylate after storage are shown in Table 2. Comparative Example 2

[00222] 40.0000 g of a methyl methacrylate reagent (water concentration: 240 ppm) were used as a methyl methacrylate-containing composition and stored as in Example 1. The amounts of methyl methacrylate and methyl pyruvate dimers produced in the methyl methacrylate-containing composition after storage are shown in Table 2. Comparative Example 3

[00223] A B-1 solution was prepared in the same way as in Example 1.

[00224] Using diacetyl as component C, 0.0205 g of component C were added to 9.9913 g of a methyl methacrylate reagent (water concentration: 240 ppm) to prepare a methyl methacrylate solution (solution C-1). The concentration of component C in solution C-1 is shown in Table 1.

[00225] Next, 0.2151 g of solution B-1 and 0.2069 g of solution C-1 were added to 40.0218 g of a methyl methacrylate reagent (water concentration: 240 ppm) to prepare a composition containing methyl methacrylate. The concentrations of the components in the composition containing methyl methacrylate are shown in Table 2.

[00226] The resulting composition containing methyl methacrylate was stored as in Example 1. The amounts of methyl methacrylate and methyl pyruvate dimers produced in the composition containing methyl methacrylate after storage are shown in Table 2. Petition 870230094863, dated 10 / 26 / 2023, pp. 58 / 91 52 / 58 Comparative Example 4

[00227] A solution A-1 was prepared in the same manner as in Example 1, except that a compound shown in Table 1 was used as component A, and the amounts of the reagent methyl methacrylate and component A were changed as shown in Table 1.

[00228] Next, a composition containing methyl methacrylate was prepared in the same manner as in Example 29, except that the amounts of the methyl methacrylate reagent and solution A-1 were altered as shown in Table 2. The concentrations of the components in the methyl methacrylate-containing composition are shown in Table 2.

[00229] The composition containing methyl methacrylate obtained was stored as in Example 1. The amounts of methyl methacrylate and methyl pyruvate dimers produced in the composition containing methyl methacrylate after storage are shown in Table 2. Comparative Example 5

[00230] A B-1 solution was prepared in the same manner as in Example 1, except that the quantities of the methyl methacrylate reagent and component B were altered as shown in Table 1.

[00231] Next, a composition containing methyl methacrylate was prepared in the same manner as in Example 24, except that the amounts of the methyl methacrylate reagent, component A, and solution B-1 were altered as shown in Table 2. The concentrations of the components in the composition containing methyl methacrylate are shown in Table 2.

[00232] The composition containing methyl methacrylate obtained was stored as in Example 1. The amounts of dimers of Petition 870230094863, dated 10 / 26 / 2023, pp. 59 / 91 53 / 58 Methyl methacrylate and methyl pyruvate produced in the composition containing methyl methacrylate after storage are shown in Table 2. Comparative Example 6

[00233] A solution A-1 was prepared in the same way as in Example 1.

[00234] A B-1 solution was prepared in the same manner as in Example 1, except that the quantities of the methyl methacrylate reagent and component B were altered as shown in Table 1.

[00235] Next, 0.1106 g of solution A-1, 0.0993 g of solution B-1 and 0.2937 g of pure water were added to 20.0064 g of a methyl methacrylate reagent (water concentration: 240 ppm) to prepare a methyl methacrylate-containing composition. The concentrations of the components in the methyl methacrylate-containing composition are shown in Table 2.

[00236] The composition containing methyl methacrylate obtained was stored as in Example 1. The amounts of methyl methacrylate and methyl pyruvate dimers produced in the composition containing methyl methacrylate after storage are shown in Table 2. Petition 870230094863, dated 10 / 26 / 2023, pp. 60 / 91 Table 1 Solution A-1 Solution B-1 Solution C-1 Amount of MMA reagent added [g] Component A Amount of MMA reagent added [g] Component B Amount of MMA reagent added [g] Component C Compound name Amount added [g] Concentration [ppm] Compound name Amount added [g] Concentration [ppm] Compound name Amount added [g] Concentration [ppm] Example 1 10.0701 Methyl acrylate 0.0186 1844 10.0026 2,4-dimethyl-6-t-butylphenol 0.0228 2274 — — — — Example 2 10.0335 Ethyl methacrylate 0.0197 1960 10.0026 2,4-dimethyl-6-t-butylphenol 0.0228 2274 — — — — Example 3 10.0155 Methyl crotonate Example 4: Isobutyl methacrylate 0.0198 1974 10.0026 2,4-dimethyl-6-t-butylphenol 0.0228 2274 — — — — Example 5: Butyl methacrylate 0.0213 2121 10.0026 2,4-dimethyl-6-t-butylphenol 0.0228 2274 — — — — Example 6: Propyl methacrylate 0.0205 2044 10.0026 2,4-dimethyl-6-t-butylphenol 0,Example 7 10.0197 Isopropenyl methyl ketone 0.0243 2419 10.0026 2,4-dimethyl-6-t-butylphenol 0.0228 2274 — — — — Example 8 10.0124 Methyl 3,3-dimethylacrylate 0.0201 2003 10.0026 2,4-dimethyl-6-t-butylphenol 0.0228 2274 — — — — Example 9 10.0058 Isopentyl methacrylate 0.0217 2164 10.0026 2,4-dimethyl-6-t-butylphenol 0.0228 2274 — — — — Example 10 10.0056 Methacrylic acid 0.0210 2094 40.008 2,4-dimethyl-6-t-butylphenol 0.0828 2065 — — — — Example 11 10.0040 Methyl cinnamate 0.0220 2194 40.008 2,4-dimethyl-6-t-butylphenol 0.0828 2065 — — — — Example 12 10.0169 Methyl 3-methoxyacrylate 0.0219 2182 40.008 2,4-dimethyl-6-t-butylphenol 0.0828 2065 — — — — Example 13 10.0128 Dimethyl fumarate 0.0223 2222 40.008 2,4-dimethyl-6-t-butylphenol 0.0828 2065 — — — — Example 14 10.1271 Methyl 1-cyclohexene-1-carboxylate 0.0246 2423 40.008 2,4-dimethyl-6-t-butylphenol 0.0828 2065 — — — — Example 15 10.0162 Methacrylamide 0.0204 2033 40.008 2,4-dimethyl-6-t-butylphenol 0,0828 2065 — — — — Example 16 10.0701 Methyl acrylate 0.0186 1844 10.0051 4-methoxyphenol 0.0191 1905 — — — — Example 17 10.0701 Methyl acrylate 0.0186 1844 10.0238 Hydroquinone 0.0233 2319 — — — — Example 18 10.0701 Methyl acrylate 0.0186 1844 10.0204 Phenothiazine 0.0238 2370 — — — — Example 19 10.0701 Methyl acrylate 0.0186 1844 10.0021 4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl 0.0202 2016 — — — — Example 20 10.0701 Methyl acrylate 0.0186 1844 10.1244 N,N-diphenylamine 0.0222 2188 — — — —, 54 / 58 Petition 870230094863, dated 10 / 26 / 2023, pp. 61 / 91 Solution A-1 Solution B-1 Solution C-1 Amount of MMA reagent added [g] Component A Amount of MMA reagent added [g] Component B Amount of MMA reagent added [g] Component C Compound name Amount added [g] Concentration [ppm] Compound name Amount added [g] Concentration [ppm] Compound name Amount added [g] Concentration [ppm] Example 21 10.0701 Methyl acrylate 0.0186 1844 10.0077 N-nitrosodiphenylamine 0.0208 2074 — — — — Example 22 10.0701 Methyl acrylate 0.0186 1844 10.0061 Triphenyl phosphite 0.0223 2224 — — — — Example 23 10.0701 Methyl acrylate 0.0186 1844 Example 24 — — — — Example 25 — — — — Example 26 — — — — Example 27 — — — — Example 28 — — — — 10.0026 2,4-dimethyl-6-t-butylphenol 0.0228 2274 — — — — 2,4-dimethyl-6-t-butylphenol 0.0829 2067 — — — — Example 28 10.0701 Methyl acrylate 0.0186 1844 40.0221 2,4-dimethyl-6-t-butylphenol 0.0829 2067 — — — — Example 29 10.0701 Methyl acrylate 0.0186 1844 — — — — — — — — Comparative Example 1 — — — — 10.0026 2,4-dimethyl-6-t-butylphenol 0.0228 2274 — — — — Comparative Example 2 — — — — — — — — — — — — Comparative Example 3 — — — — 10.0026 2,4-dimethyl-6-t-butylphenol 0.0228 2274 9.9913 Diacetyl 0.0205 2048 Comparative Example 4 10.0197 Isopropenyl methyl ketone 0.0243 2419 — — — — — — — — Comparative Example 5 — — — — 40.0221 2,4-dimethyl-6-t-butylphenol 0.0829 2067 — — — — Comparative Example 6 10.0701 Methyl acrylate 0.0186 1844 40.0221 2,4-dimethyl-6-t-butylphenol 0.0829 2067 — — — —, 55 / 58 Petition 870230094863, dated 10 / 26 / 2023, pp. 62 / 91 Table 2 Amount added [g] Composition containing MMA Amount of MMA dimer produced [ppm] Amount of methyl pyruvate produced [ppm] MMA Component A Component B Component C MB / MA MMA Reagent Solution A1 Solution B1 Solution C-1 Component A Pure water Concentration [%] Compound name Concentration MA [pmol / L] Compound name Concentration MB [pmol / L] Compound name Concentration [pmol / L] Example 1 20.0348 0.1072 0.1062 — — — 99.97 Methyl acrylate 107 2,4-dimethyl-6-t-butylphenol 63 — — 0.590 20 2 Example 2 20.0034 0.1009 0.0950 — — — 99.97 Ethyl methacrylate 81 2,4-dimethyl-6-t-butylphenol 57 — — Example 3 20.0017 0.1050 0.1031 — — — 99.97 Methyl crotonate 101 2,4-dimethyl-6-t-butylphenol 61 — — 0.608 20 2 Example 4 20.0115 0.1009 0.1037 — — — 99.97 Isobutyl methacrylate 65 2,4-dimethyl-6-t-butylphenol 62 — — 0.945 15 2 Example 5 20.0393 0.1021 0.1015 — — — 99.97 Butyl methacrylate 71 2,4-dimethyl-6-t-butylphenol 60 — — 0.850 16 0 Example 6 20.0301 0.1050 0.1050 — — — 99,97 Propyl methacrylate 78 2,4-dimethyl-6-t-butylphenol 62 — — 0.800 22 3 Example 7 20.0049 0.1058 0.1001 — — — 99.97 Isopropenyl methyl ketone 142 2,4-dimethyl-6-t-butylphenol 60 — — 0.420 22 4 Example 8 20.0514 0.1023 0.1014 — — — 99.97 Methyl 3,3-dimethylacrylate 84 2,4-dimethyl-6-t-butylphenol 60 — — 0.720 14 5 Example 9 20.0118 0.1031 0.1077 — — — 99.97 Methacrylate of Isopentyl 67 2,4-dimethyl-6-t-butylphenol 64 — — 0.962 17 1 Example 10 10.0100 0.0533 0.0520 — — — 99.97 Methacrylic acid 121 2,4-dimethyl-6-t-butylphenol 56 — — 0.465 19 7 Example 11 10.0027 0.0533 0.0514 — — — 99.97 Methyl cinnamate 67 2,4-dimethyl-6-t-butylphenol 56 — — 0.826 21 8 Example 12 10.0003 0.0509 0.0529 — — — 99.97 Methyl 3-methoxyacrylate 89 2,4-dimethyl-6-t-butylphenol 57 — — 0.641 18 8 Example 13 10.0041 0.0541 0.0539 — — — 99.97 Dimethyl fumarate 78 2,4-dimethyl-6-t-butylphenol 58 — — 0.749 22 11 Example 14 10.0403 0.0520 0.0559 — — — 99.97 Methyl 1-cyclohexene-1-carboxylate 84 2,4-dimethyl-6-t-butylphenol 60 — — 0.720 23 8 Example 15 10.0035 0.0511 0.0533 — — — 99.97 Methacrylamide 114 2,4-dimethyl-6-t-butylphenol 58 — — 0.506 27 3 Example 16 20.0077 0.1034 0.1051 — — — 99.97 Methyl acrylate 103 4-methoxyphenol 75 — — 0.728 20 0 Example 17 20.0083 0.1040 0.1043 — — — 99.97 Methyl acrylate 104 Hydroquinone 103 — — 0.986 22 1 Example 18 20.0075 0.1040 0.1009 — — — 99.97 Methyl acrylate 104 Phenothiazine 56 — — 0.539 23 1 Example 19 10.0175 0.0506 0.0526 — — — 99.97 Methyl acrylate 101 4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl 57 — — 0.568 1 7, 56 / 58 Petition 870230094863, dated 10 / 26 / 2023, pp. 63 / 91 Example 20 10.0009 0.0527 0.0510 — — — 99.97 Methyl acrylate 105 N,N-diphenylamine 62 — — 0.584 7 0 Example 21 10.0182 0.0526 0.0511 — — — 99.97 Methyl acrylate 105 N-nitrosodiphenylamine 50 — — 0.475 1 0 Example 22 10.0052 0.0537 0.0508 — — — 99.97 Methyl acrylate 107 Triphenyl phosphite 34 — — 0.317 0 19 Example 23 19.0124 1.0068 0.1072 — — — 99.97 Methyl acrylate 1011 2,4-dimethyl-6-t-butylphenol 64 — — 0.063 25 4 Example 24 20.0166 — 0.1086 — 0.0205 — 99.87 Methyl acrylate 11158 2,4-dimethyl-6-t-butylphenol 65 — — 0.006 20 4 Example 25 10.0251 — 0.0616 — 0.0744 — 99.24 Methyl acrylate 80288 2,4-dimethyl-6-t-butylphenol 66 — — 0.001 23 4 Example 26 19.0025 0.1013 1.0023 — — — 99.96 Methyl acrylate 102 2,4-dimethyl-6-t-butylphenol 600 — — 5.894 21 0 Example 27 7.5077 0.0554 2.5301 — — — 99.92 Methyl acrylate 111 2,4-dimethyl-6-t-butylphenol 2744 — — 24.726 24 2 Example 28 3.9990 0.0538 6.0154 — — — 99.85 Methyl acrylate 108 2,4-dimethyl-6-t-butylphenol 6539 — — 60,536 20 0 Example 29 20.0196 0.1048 — — — — 99.98 Methyl acrylate 105 — — — — — 21 2 Comparative Example 1 40.0273 — 0.2213 — — — 99.97 — — 2,4-dimethyl-6-t-butylphenol 66 — — — 29 2 Comparative Example 2 40.0000 — — — — — 99.98 — — — — — — — 0 25 Comparative Example 3 40.0218 — 0.2151 0.2069 — — 99.97 — — 2,4-dimethyl-6-t-butylphenol 64 Diacetyl 115 — 0 1056 Comparative Example 4 40.0115 0.2027 — — — — 99.97 Isopropenyl methyl ketone 137 — — — — — 17 15 Comparative Example 5 20.0295 — 0.1143 — 0.3109 — 98.46 Methyl acrylate 166666 2,4-dimethyl-6-t-butylphenol 61 — — 0.0004 35 2 Comparative Example 6 20.0064 0.1106 0.0993 — — 0.2937 98.54 Methyl acrylate 109 2,4-dimethyl-6-t-butylphenol 53 — — 0.486 30 4, 57 / 58 Petition 870230094863, dated 10 / 26 / 2023, pp. 64 / 91 58 / 58

[00237] As shown in Tables 1 and 2, Examples 1 to 28, in which the composition containing methyl methacrylate contains defined components A and B, show a reduction in both the production of methyl methacrylate dimers and methyl pyruvate in the methyl methacrylate compositions after storage, and can be said to have high-quality stability during storage. Example 29, containing defined concentrations of components corresponding to components A2 and A3, shows a reduction in both the production of methyl methacrylate dimers and methyl pyruvate in the methyl methacrylate composition after storage, even without a component B, and can be said to have high-quality stability during storage.

[00238] The polymeric composition comprising each composition containing methyl methacrylate obtained in each Example can be polymerized to obtain a methyl methacrylate polymer. INDUSTRIAL APPLICABILITY

[00239] According to the present invention, compositions containing methyl methacrylate that can be used, for example, as raw material for acrylic resins can be stored stably for a long period of time, which is industrially useful.

Claims

1. Composition containing methyl methacrylate, characterized in that it comprises: methyl methacrylate; an α,β-unsaturated carbonyl compound represented by the following Formula (1) (component A1); and a polymerization inhibitor (component B), wherein when the concentration of component A1 is MA1 (μmol / L) and the concentration of component B is MB (μmol / L), MB / MA1 is 0.1 or more, and the concentration of methyl methacrylate is from 99 to 99.99% by mass, R3rY^yr4 <1> R1 O wherein, in Formula (1) above, R1, R2 and R3 each independently represent a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, a hydroxy group, an alkoxy group, an amino group, a monovalent group containing a carbonyl group, an alkylthio group, or an arylthio group, R4 represents an alkyl group, an alkenyl group, an aryl group, a hydroxy group, an alkoxy group, an amino group, a monovalent group containing a carbonyl group, an alkylthio group or an arylthio group, R1 and R2, R2 and R3,and R3 and R4 may be linked together to form a ring, except when R1 = H, R2 = H, R3 = CH3 and R4 = OCH3, that is, when the α,β-unsaturated carbonyl compound represented by Formula (1) is methyl methacrylate, and H represents a hydrogen atom, C represents a carbon atom and O represents an oxygen atom. Petition 870240080876, dated 23 / 09 / 2024, page 9 / 19 2 / 8, 2. Composition containing methyl methacrylate, according to claim 1, characterized in that MA1 is from 1 to 85,000 μmol / L.

3. Composition containing methyl methacrylate, according to claim 2, characterized in that MA1 is from 10 to 40,000 μmol / L.

4. Composition containing methyl methacrylate, according to any one of claims 1 to 3, characterized in that MB is from 1 to 7,000 μmol / L.

5. Composition containing methyl methacrylate, according to claim 4, characterized in that the MB is from 10 to 5,000 pmol / L.

6. Composition containing methyl methacrylate, according to any one of claims 1 to 5, characterized in that the molecular weight of component A1 is 1,000 or less.

7. Composition containing methyl methacrylate, according to any one of claims 1 to 6, characterized in that component B is at least one polymerization inhibitor selected from the group consisting of a phenol compound, a quinone compound, a nitrobenzene compound, an N-oxyl compound, an amine compound, a phosphorus-containing compound, a sulfur-containing compound, an iron-containing compound, a copper-containing compound, and a manganese-containing compound.

8. Composition containing methyl methacrylate, according to any one of claims 1 to 7, characterized in that component B is at least one polymerization inhibitor selected from the group consisting of a phenol compound, an N-oxyl compound, an amine compound, a phosphorus-containing compound and a sulfur-containing compound.

9. Composition containing methyl methacrylate, according to Petition 870240080876, dated 09 / 23 / 2024, page 10 / 19 3 / 8 with any of claims 1 to 8, characterized in that component B is at least one polymerization inhibitor selected from the group consisting of hydroquinone, 4-methoxyphenol, 2,4-dimethyl-6-t-butylphenol, 2,6-di-t-butyl-4-methylphenol, 4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl, N,N-diphenylamino, N-nitrosodiphenylamine, triphenyl phosphite and phenothiazine.

10. Composition containing methyl methacrylate, according to any one of claims 1 to 9, characterized in that in Formula (1) above, R1-R2 and R3 are each independently a hydrogen atom, a C1-5 alkyl group, a C2-5 alkenyl group, a C1-12 aryl group, a C1-6 alkoxy group, an amino group, a monovalent group containing a carbonyl group, or a C1-5 alkylthio group; and R4 is a C1-5 alkyl group, a C2-5 alkenyl group, a C1-12 aryl group, a hydroxy group, a C1-6 alkoxy group, an amino group, a monovalent group containing a carbonyl group, or a C1-5 alkylthio group.

11. Composition containing methyl methacrylate, according to any one of claims 1 to 10, characterized in that in Formula (1) above, R1, R2 and R3 are each independently a hydrogen atom or a C1-5 alkyl group, and R4 is a C1-5 alkyl group or a C1-5 alkoxy group.

12. Composition containing methyl methacrylate, according to any one of claims 1 to 11, characterized in that in Formula (1) above, R1, R2 and R3 are each independently a hydrogen atom, a methyl group, an ethyl group, an n-propyl group or an isopropyl group, and R4 is a methyl group, a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, an isobutoxy group or an isopentoxy group.

13. Composition containing methyl methacrylate, according to any one of claims 1 to 12, characterized in that the concentration of methyl methacrylate is from 99.8 to 99.99% by mass.

14. Composition containing methyl methacrylate, according to any one of claims 1 to 13, characterized in that the composition does not contain diacetyl, or the concentration of diacetyl contained is 55 μmol / L or less.

15. Composition containing methyl methacrylate, characterized in that it comprises: methyl methacrylate; an α,β-unsaturated carboxylate ester represented by the following Formula (2) (component A2), and a polymerization inhibitor (component B), wherein the concentration of methyl methacrylate is from 99 to 99.99% by mass, when the concentration of component A2 is MA2 (pmol / L), and the concentration of component B is MB (pmol / L), MB / MA1 is 0.1 or more, and MA2 is from 1 to 40,000 pmol / L; wherein, in Formula (2) above, R5' R6 and R7 each independently represent a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, a hydroxy group, an alkoxy group, an amino group, a group Petition 870240080876, dated 23 / 09 / 2024, page.12 / 19 5 / 8 monovalent containing a carbonyl group, an alkylthio group, or an arylthio group, R8 represents an alkyl group, an alkenyl group, or an aryl group, R5 and R6, R6 and R7, and R7 and R8 may be linked together to form a ring, except when R5 = H, R6 = H, R7 = CH3, and R8 = CH3, that is, when the α,β-unsaturated carbonyl compound represented by Formula (2) is methyl methacrylate, and H represents a hydrogen atom, C represents a carbon atom, and O represents an oxygen atom.

16. Composition containing methyl methacrylate, according to claim 15, characterized in that the MA2 is from 10 to 5,000 μmol / L.

17. Composition containing methyl methacrylate, according to claim 15 or 16, characterized in that the MA2 is from 10 to 500 μmol / L.

18. Composition containing methyl methacrylate, according to any one of claims 15 to 17, characterized in that the molecular weight of component A2 is 1,000 or less.

19. Composition containing methyl methacrylate, according to any one of claims 15 to 18, characterized in that in Formula (2) above, R5, R6 and R7 are each independently a hydrogen atom, a C1-5 alkyl group, a C2-5 alkenyl group, a C1-12 aryl group, a C1-6 alkoxy group, an amino group, a monovalent group containing a carbonyl group, or a C1-5 alkylthio group, and R8 is a C1-5 alkyl group, a C2-5 alkenyl group or a C1-12 aryl group.

20. Composition containing methyl methacrylate, according to Petition 870240080876, dated 09 / 23 / 2024, page 13 / 19 6 / 8 with any of claims 15 to 19, characterized in that in Formula (2) above, R5, R6 and R7 are each independently a hydrogen atom or a C1-5 alkyl group, and R8 is a C1-5 alkyl group.

21. Composition containing methyl methacrylate, according to any one of claims 15 to 20, characterized in that in Formula (2) above, R5, R6 and R7 are each independently a hydrogen atom, a methyl group, an ethyl group, an n-propyl group or an isopropyl group, and R8 is a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group or an isopentyl group.

22. Composition containing methyl methacrylate, according to any one of claims 15 to 21, characterized in that in Formula (2) above, R5, R6 and R7 are each independently a hydrogen atom or a methyl group, and R8 is a methyl group.

23. Composition containing methyl methacrylate, according to any one of claims 15 to 22, characterized in that the concentration of methyl methacrylate is from 99.8 to 99.99% by mass.

24. Composition containing methyl methacrylate, according to any one of claims 15 to 23, characterized in that the composition does not contain diacetyl, or the concentration of diacetyl contained is 55 μmol / L or less. Petition 870240080876, dated 23 / 09 / 2024, page 14 / 19 7 / 8 25. Composition containing methyl methacrylate, characterized in that it comprises: methyl methacrylate; and at least one compound (component A3) selected from the group consisting of methyl acrylate, butyl acrylate, ethyl methacrylate, methyl crotonate, cis-methyl crotonate, isobutyl methacrylate, butyl methacrylate, propyl methacrylate, isopentyl methacrylate, methyl 2-methylene-3-butenoate, methyl 3,3-dimethylacrylate, methyl 2-ethylacrylate, methyl 2-pentenoate, methyl cinnamate, methyl 3-methoxyacrylate, dimethyl fumarate, methyl 1-cyclohexene-1-carboxylate, methacrylamide, acrylic acid, crotonic acid, cis-crotonic acid, 3,3-dimethylacrylic acid, 2-ethylacrylic acid, 2-methylene-3-butenoic acid and trans-3-hexen-2-one, wherein The concentration of methyl methacrylate is 99 to 99.99% by mass, and when the concentration of component A3 is MA3 (pmol / L), MA3 is 1 to 10,000 pmol / L; 26. Composition containing methyl methacrylate, according to claim 25, characterized in that the MA3 is from 10 to 5,000 pmol / L.

27. Composition containing methyl methacrylate, according to claim 25 or 26, characterized in that the MA3 is from 10 to 500 pmol / L.

28. Composition containing methyl methacrylate, according to any one of claims 25 to 27, characterized in that component A3 is at least one selected from the group consisting of methyl acrylate, methyl crotonate, acrylic acid and crotonic acid.

29. Composition containing methyl methacrylate, according to any one of claims 25 to 28, characterized in that the concentration of methyl methacrylate is 99.8 to 99.99% by mass.

30. Composition containing methyl methacrylate, according to any one of claims 25 to 29, characterized in that the composition does not contain diacetyl, or the concentration of diacetyl contained is 55 μmol / L or less.

31. A method for producing a methyl methacrylate polymer, characterized in that it comprises a polymerization step of a polymeric composition comprising a composition containing methyl methacrylate, as defined in any one of claims 1 to 30.

32. A method for producing a methyl methacrylate polymer according to claim 31, characterized in that the polymeric composition comprises 0.01 parts by mass or more of a monomer that can be copolymerized with methyl methacrylate relative to 100 parts by mass of methyl methacrylate.