JP6790436B2 - Method for Producing (Meta) Acrylic Resin Composition, Resin Mold, and (Meta) Acrylic Resin Composition - Google Patents

Description

The present invention relates to a (meth) acrylic resin composition, a resin molded product, and a method for producing a (meth) acrylic resin composition.

(Meta) acrylic resin containing methyl methacrylate as a main component is excellent in transparency, heat resistance and weather resistance, and has well-balanced performance in resin physical properties such as mechanical strength, thermal properties and molding processability. Have. Therefore, it is used in many applications such as lighting materials, optical materials, signboards, displays, decorative members, building members, etc., and flame retardancy and heat resistance are required for these applications.

Therefore, studies have been conducted to impart flame retardancy to (meth) acrylic resin products without impairing the transparency, heat resistance, or weather resistance that are the characteristics of (meth) acrylic resins.

Patent Document 1 proposes a flame-retardant methacrylic resin plate composed of a methacrylic resin containing a heat resistance improving monomer and a halide phosphate, and dicyclopentanyl (meth) as the heat resistance improving monomer. ) Acrylics are disclosed.

Patent Document 2 proposes a flame-retardant methacrylic resin plate composed of a methacrylic resin containing an alicyclic methacrylate and a halide phosphate.

Patent Document 3 proposes a (meth) acrylic polymer containing methyl methacrylate and isobornyl (meth) acrylate, and a flame-retardant methacrylic resin plate containing a flame-resistant polymer phosphorus compound.

Japanese Unexamined Patent Publication No. 2011-46835 JP-A-2015-86250 Special Publication No. 44-29382

However, although the methacrylic resin plate described in Patent Document 1 has improved flame retardancy, the heat resistance of the resin plate is not sufficient because the content of the heat resistance improving monomer is small.

The methacrylic resin plate described in Patent Document 2 has improved flame retardancy, but the weather resistance of the resin plate is not sufficient.

Further, although the methacrylic resin plate described in Patent Document 3 can obtain heat resistance, its flame retardancy is not sufficient.

An object of the present invention is to solve these problems. That is, the first object of the present invention is to obtain a (meth) acrylic resin composition having heat resistance, weather resistance, and flame retardancy, and a resin molded product composed of the (meth) acrylic resin composition. To provide.

A second object of the present invention is to provide a method for stably producing the above-mentioned (meth) acrylic resin composition.

The first gist of the present invention is a (meth) acrylic resin composition containing a (meth) acrylic polymer (P) and a phosphorus atom-containing compound (C), wherein the (meth) acrylic polymer (meth) P) is a repeating unit derived from methyl methacrylate and a repeating unit derived from a monomer (B) having two or more vinyl groups with respect to the total mass of the (meth) acrylic polymer (P). The repeating unit derived from the (meth) acrylic acid ester (M) having an aromatic hydrocarbon group or an alicyclic hydrocarbon group having 3 to 20 carbon atoms in the side chain is the same as that of the (meth) acrylic polymer (P). A (meth) acrylic resin composition containing 5.0% by mass or more and 15.0% by mass or less with respect to the total mass .
The (meth) acrylic polymer (P) is used as a repeating unit derived from the (meth) acrylic acid ester (M).
A repeating unit derived from a methacrylic acid ester (M1) having an aromatic hydrocarbon group or an alicyclic hydrocarbon group having 3 to 20 carbon atoms in a side chain is added to the total mass of the (meth) acrylic polymer (P). On the other hand, 4.0% by mass or more and 14% by mass or less, and
A repeating unit derived from an acrylic acid ester (M2) having an aromatic hydrocarbon group or an alicyclic hydrocarbon group having 3 to 20 carbon atoms in a side chain is added to the total mass of the (meth) acrylic polymer (P). On the other hand, it contains 1.0% by mass or more and 5.0% by mass or less, and
The total of the repeating unit derived from the methacrylic acid ester (M1) and the repeating unit derived from the acrylic acid ester (M2) is based on the total mass of the (meth) acrylic polymer (P).
5.0% by mass or more and 15% by mass or less,
The phosphorus atom-containing compound (C) is in a (meth) acrylic resin composition, which is at least one selected from a phosphoric acid ester and a phosphonic acid ester .

Further, the methacrylic resin composition of the present invention may contain 0.001 part by mass or more and 0.35 part by mass or less of the inorganic pigment (D) with respect to 100 parts by mass of the (meth) acrylic polymer (P). it can.

Further, the methacrylic resin composition of the present invention may contain 0.1 part by mass or more and 4.0 parts by mass or less of the resin fine particles (F) with respect to 100 parts by mass of the (meth) acrylic polymer (P). it can.

The second gist of the present invention is a resin molded product made of the (meth) acrylic resin composition.

A third gist of the present invention is to polymerize a polymerizable monomer composition (S1) and a polymerizable composition (S2) containing a phosphorus atom-containing compound (C) to obtain a (meth) acrylic resin composition. In the method for producing, the polymerizable monomer composition (S1) contains methyl methacrylate, a monomer (B) having two or more vinyl groups, and a repeating unit derived from methyl methacrylate as main components. The polymer (P1) containing the polymer (P1) is 5% by mass or more and 40% by mass or less based on the total mass of the polymerizable monomer composition (S1), and is an aromatic hydrocarbon group or an alicyclic having 3 to 20 carbon atoms. having the formula hydrocarbon group in its side chain (meth) acrylic acid ester (M), relative to the total weight of the polymerizable monomer composition (S1), 5.0 wt% to 15.0 wt% A method for producing a (meth) acrylic resin composition containing the following .
The (meth) acrylic polymer (P1) is 90% by mass of a repeating unit derived from methyl methacrylate with respect to the total mass of the copolymer of methyl methacrylate and the (meth) acrylic polymer (P1). At least one selected from (co) polymers including the above,
The polymerizable monomer composition (S1) is a methacrylic acid having an aromatic hydrocarbon group or an alicyclic hydrocarbon group having 3 to 20 carbon atoms in a side chain as the (meth) acrylic acid ester (M). It contains an ester (M1) and an acrylic acid ester (M2) having an aromatic hydrocarbon group or an alicyclic hydrocarbon group having 3 to 20 carbon atoms in a side chain, and
The methacrylic acid ester (M1) was added to the total mass of the polymerizable monomer composition (S1).
4.0% by mass or more and 14.0% by mass or less, and 1.0% by mass or more and 5.0 of the acrylic acid ester (M2) with respect to the total mass of the polymerizable monomer composition (S1). Contains less than% by mass,
The method for producing a (meth) acrylic resin composition, wherein the phosphorus atom-containing compound (C) is at least one selected from a phosphoric acid ester and a phosphonic acid ester .

INDUSTRIAL APPLICABILITY According to the present invention, a (meth) acrylic resin composition having good heat resistance and weather resistance and further high flame retardancy, and a resin molded product composed of the (meth) acrylic resin composition are stably provided. can do. Such a resin molded body is suitable for applications that require high flame retardancy, heat resistance, and weather resistance, such as signboards and lighting.

Hereinafter, the present invention will be described in detail. In the present invention, "(meth) acrylate" and "(meth) acrylic acid" are at least one selected from "acrylate" and "methacrylate" and at least one selected from "acrylic acid" and "methacrylic acid", respectively. Means.

Further, "monomer" means an unpolymerized compound, and "repeating unit" means a unit derived from the monomer formed by polymerizing the monomer. The repeating unit may be a unit directly formed by a polymerization reaction, or a part of the unit may be converted into another structure by processing a polymer.

<(Meta) acrylic resin composition>
As an example of an embodiment of the (meth) acrylic resin composition of the present invention, a (meth) acrylic resin composition containing a (meth) acrylic polymer (P) described later and a phosphorus atom-containing compound (C) described later. I can exemplify things.

In the (meth) acrylic resin composition, the total content of the (meth) acrylic polymer (P) and the phosphorus atom-containing compound (C) is the total mass of the (meth) acrylic resin composition. Is 100% by mass, and 90% by mass or more can be contained.

The (meth) acrylic resin composition contains 5.0 parts by mass or more and 35 parts by mass of the phosphorus atom-containing compound (C) with respect to 100 parts by mass of the (meth) acrylic polymer (P). Can be done.
When the lower limit of the content of the phosphorus atom-containing compound (C) with respect to 100 parts by mass of the (meth) acrylic polymer is 5.0 parts by mass or more, the flame retardancy of the resin molded product is good. Further, if the upper limit of the content of the phosphorus atom-containing compound (C) with respect to 100 parts by mass of the (meth) acrylic polymer is 35 parts by mass or less, the heat resistance of the resin molded product is good.

<Resin molded product>
By using the (meth) acrylic resin composition of the present invention, a resin molded product having excellent flame retardancy, heat resistance and weather resistance can be obtained.

<(Meta) acrylic polymer (P)>
The (meth) acrylic resin composition in the present invention contains the following (meth) acrylic polymer (P) as one of the constituent components. By containing the (meth) acrylic polymer (P) as one of the constituent components, it is possible to obtain a resin molded product having excellent heat resistance and flame retardancy due to a synergistic effect with other constituent components described later. It will be possible.

The (meth) acrylic polymer (P) is a polymer containing the following (1) to (3).
(1) Repeating unit derived from methyl methacrylate (2) Repeating unit derived from monomer (B) having two or more vinyl groups (3) Aromatic hydrocarbon group or alicyclic hydrocarbon having 3 to 20 carbon atoms Repeating unit derived from (meth) acrylic acid ester (M) having a group in the side chain 5.0% by mass or more and 15% by mass or less

The lower limit of the content of the repeating unit derived from methyl methacrylate in the (meth) acrylic polymer (P) is not particularly limited, but the impact resistance and mechanical strength of the resin molded product are improved. Therefore, 81% by mass or more is preferable with respect to the total mass of the (meth) acrylic polymer (P). The upper limit of the content is not particularly limited, but is preferably 95% by mass or less because the flame retardancy of the resin molded product is improved. The above upper limit value and lower limit value can be arbitrarily combined.

The lower limit of the content of the repeating unit derived from the monomer (B) in the (meth) acrylic polymer (P) is not particularly limited, but the flame retardancy of the resin molded product is improved. It is preferably 0.05% by mass or more, more preferably 0.12% by mass or more, based on the total mass of the (meth) acrylic polymer (P). The upper limit of the content is not particularly limited, but is preferably 0.40% by mass or less, more preferably 0.36% by mass or less, because the impact resistance and mechanical strength of the resin molded product are improved. The above upper limit value and lower limit value can be arbitrarily combined. The specific monomer (B) will be described later.

<(Meta) Acrylic Ester (M)>
In the present invention, the (meth) acrylic acid ester (M) is a monofunctional (meth) acrylic acid ester having an aromatic hydrocarbon group or an alicyclic hydrocarbon group having 3 to 20 carbon atoms in a side chain. .. By containing the (meth) acrylic acid ester (M), the flame retardancy of the resin molded product becomes good.

Specific examples include cyclohexyl (meth) acrylate, bornyl (meth) acrylate, norbornyl (meth) acrylate, isobornyl (meth) acrylate, adamantyl (meth) acrylate, dimethyl adamantyl (meth) acrylate, and methacrylic acid. Methylcyclohexyl, norbornylmethyl (meth) acrylate, menthyl (meth) acrylate, fentyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, (meth) acrylic Dicyclopentenyloxyethyl acid, cyclodecyl (meth) acrylate, 4-t-butylcyclohexyl (meth) acrylate, trimethylcyclohexyl (meth) acrylate, benzyl (meth) acrylate, phenoxyethyl (meth) acrylate, etc. Examples thereof include (meth) acrylic acid esters and derivatives thereof. These can be used alone or in combination of two or more.

The reason why the flame retardancy of the resin molded product is improved by including the repeating unit derived from the (meth) acrylic acid ester (M) in the (meth) acrylic polymer (P) is not clear. When heat is applied, the structural unit derived from the (meth) acrylic acid ester (M) contained in the meta) acrylic polymer (P) is decomposed and the side chains are desorbed and converted into a methacrylic acid structural unit. The methacrylic acid structural unit interacts with the phosphorus atom-containing compound (C) to synergistically enhance the flame retardancy improving effect of the phosphorus atom-containing compound (C), whereby the (meth) acrylic system is used. It is presumed that when the resin composition is burned, the amount of carbonized material (char) produced increases, and the flame retardancy is improved. Carbide (char) enhances the flame retardancy of the (meth) acrylic resin composition. Further, when the desorbed side chain of the (meth) acrylic acid ester (M) burns, the surrounding oxygen is consumed, the combustion field becomes oxygen-deficient, and the flame retardancy of the resin composition is further enhanced. It is estimated to be.

The lower limit of the content of the repeating unit derived from the (meth) acrylic acid ester (M) in the (meth) acrylic polymer (P) is not particularly limited, but the flame retardancy of the resin molded product is improved. Therefore, 5.0% by mass or more is preferable, and 6.0% by mass or more is more preferable with respect to the total mass of the polymer (P). It is preferably 15% by mass or less, more preferably 10% by mass or less, because the impact resistance and mechanical strength of the resin molded product are improved.

As the (meth) acrylic polymer (P) containing the (meth) acrylic acid ester (M), the (meth) acrylic acid ester (M) is an aromatic hydrocarbon group or a fat having 3 to 20 carbon atoms. A repeating unit derived from a methacrylic acid ester (M1) having a cyclic hydrocarbon group in the side chain, and an acrylic acid ester (M2) having an aromatic hydrocarbon group or an alicyclic hydrocarbon group having 3 to 20 carbon atoms in the side chain. ) Derived (meth) acrylic polymer (P) containing a repeating unit can be used.

The methacrylic acid ester (M1) and the acrylic acid ester (M2) interact with the phosphorus atom-containing compound (C) to synergistically enhance the flame retardancy improving effect of the phosphorus atom-containing compound (C). The flame retardancy of the resin molded product can be improved by reducing the water absorption rate of the resin molded product.

Further, since the unreacted monomer in the (meth) acrylic resin composition after polymerization tends to be reduced by containing the acrylic acid ester (M2), the weather resistance of the obtained resin molded product is improved. It will be good.

The (meth) acrylic polymer (P) containing the (meth) acrylic acid ester (M) is the methacrylic acid ester (M1) with respect to the total mass of the (meth) acrylic polymer (P). ) Derived from 4.0% by mass or more and 14% by mass or less, and 1.0% by mass or more and 5.0% by mass or less of the repeating unit derived from the acrylic acid ester (M2), and said methacrylic acid ester. The total of the repeating unit derived from (M1) and the repeating unit derived from the acrylic acid ester (M2) is contained in an amount of 5.0% by mass or more and 15% by mass or less based on the total mass of the polymer (P). A meth) acrylic polymer (P) can be used.

The lower limit of the content of the repeating unit derived from the methacrylic acid ester (M1) in the (meth) acrylic polymer (P) is not particularly limited, but the flame retardancy and heat resistance of the resin molded product are good. Therefore, it is preferably 4.0% by mass or more, more preferably 5.0% by mass or more, based on the total mass of the polymer (P). The upper limit of the content is not particularly limited, but is preferably 14% by mass or less, more preferably 13% by mass or less, because the weather resistance of the resin molded product is good. The above upper limit value and lower limit value can be arbitrarily combined.

The lower limit of the content of the repeating unit derived from the acrylic acid ester (M2) in the (meth) acrylic polymer (P) is not particularly limited, but the flame retardancy and weather resistance of the resin molded product are improved. , 1.0% by mass or more is preferable, and 2.0% by mass or more is more preferable with respect to the total mass of the polymer (P). The upper limit of the content is not particularly limited, but 5.0% by mass or less is preferable with respect to the total mass of the polymer (P) because the heat resistance of the resin molded product is good, and 4.0% by mass. The following is more preferable. The above upper limit value and lower limit value can be arbitrarily combined.

The lower limit of the total content of the repeating unit derived from the methacrylic acid ester (M1) and the repeating unit derived from the acrylic acid ester (M2) in the (meth) acrylic polymer (P) is not particularly limited, but the resin. Since the flame retardancy of the molded product is improved, 5.0% by mass or more is preferable with respect to the total mass of the polymer (P). The upper limit of the content is not particularly limited, but since the heat resistance and weather resistance of the resin molded product are good, it is preferably 15% by mass or less, preferably 11.0% by mass, based on the total mass of the polymer (P). % Or less is more preferable. The above upper limit value and lower limit value can be arbitrarily combined.

In the (meth) acrylic resin composition of the present invention, examples of the methacrylic acid ester (M1) include dicyclopentanyl methacrylate, isobornyl methacrylate, cyclohexyl methacrylate, benzyl methacrylate and the like, but are particularly limited. It is not something that is done. Among them, at least one selected from cyclohexyl methacrylate and isobornyl methacrylate is preferable because the effect of improving the flame retardancy and flame retardancy of the resin molded product is particularly excellent.

In the (meth) acrylic resin composition of the present invention, examples of the methacrylic acid ester (M2) include dicyclopentanyl acrylate, isobornyl acrylate, cyclohexyl acrylate, and benzyl acrylate. It is not limited to. Among them, at least one selected from cyclohexyl acrylate and isobornyl acrylate (hereinafter, "monomer (M2')") is particularly excellent in improving the flame retardancy and heat resistance of the resin molded product. In addition, when used in combination with the methacrylic acid ester (M1), it has the effect of reducing the unpolymerized product of the methacrylic acid ester (M1) and is excellent in the effect of improving the weather resistance of the resin molded product. preferable.

The lower limit of the content of the repeating unit derived from the monomer (M2') is not particularly limited, but is 1.0% by mass with respect to the total mass of the (meth) acrylic polymer (P). With the above, the flame retardancy and weather resistance of the resin molded product can be improved, which is preferable, and 2.0% by mass or more is more preferable. On the other hand, the upper limit of the content is not particularly limited, but if the content is 5.0% by mass or less, it is preferable because the heat resistance of the resin molded product can be further improved, and 4.0% by mass or less is more preferable. preferable. The above upper limit value and lower limit value can be arbitrarily combined.

<Monomer (B)>
The monomer (B) is a monomer having two or more vinyl groups, and is one of the constituents of the (meth) acrylic resin composition of the present invention. When the (meth) acrylic polymer (P) contains a structural unit derived from the monomer (B), the flame retardancy of the resin molded product can be further improved.

As the monomer (B), a bifunctional (meth) acrylate is preferable. For example, ethylene glycol di (meth) acrylate, 1,2-propylene glycol di (meth) acrylate, 1,3-butylene glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate. Examples thereof include alkanediol di (meth) acrylates such as meta) acrylates and tricyclodecanedimethanol di (meth) acrylates. These can be used alone or in combination of two or more.

In particular, at least one monomer selected from ethylene glycol di (meth) acrylate and neopentyl glycol di (meth) acrylate has excellent handleability of raw materials and flame retardancy of the resin molded product. It is preferable because it can be made better.

<Copolymerizable monomer>
In the present invention, if necessary, a repeating unit derived from a monomer copolymerizable with methyl methacrylate and the (meth) acrylic acid ester (M) is used as the total mass of the (meth) acrylic polymer (P). On the other hand, it can be contained in the acrylic polymer (P) in a range of more than 0% by mass and 10% by mass or less.

Examples of the copolymerizable monomer include ethyl (meth) acrylate, isopropyl (meth) acrylate, t-butyl (meth) acrylate, i-butyl (meth) acrylate, and n (meth) acrylate. -Unsaturated carboxylic acids such as butyl, (meth) acrylic acid, maleic acid and itaconic acid, acid anhydrides such as maleic anhydride and itaconic anhydride, maleimide derivatives such as N-phenylmaleimide and N-cyclohexylmaleimide, vinyl acetate , Vinyl esters such as vinyl benzoate, vinyl chloride, vinylidene chloride and derivatives thereof, nitrogen-containing monomers such as methacrylamide and acrylonitrile, epoxy group-containing monomers such as glycidyl acrylate (meth) acrylate, and styrene, α. − Examples include aromatic vinyl compounds such as methylstyrene.

<Phosphorus atom-containing compound (C)>
In the present invention, in order to enhance the flame retardancy of the resin molded product, it is preferable that the (meth) acrylic resin composition contains a phosphorus atom-containing compound as one of the constituent components. A flame-retardant synergistic effect can be obtained by using a phosphorus atom-containing compound having a flame-retardant improving effect in combination with a repeating unit derived from the monomer (B) and a repeating unit derived from the (meth) acrylic acid ester (M). , The flame retardancy of the resin molded product can be improved.

Examples of the phosphorus atom-containing compound (C) include a phosphoric acid ester compound (hereinafter, abbreviated as “phosphate ester”) and a phosphonic acid ester compound (hereinafter, abbreviated as “phosphonic acid ester”). Can be done. Specific examples thereof include, but are not limited to, the following compounds. These compounds can be used alone or in combination of two or more.

1) Halogen-free phosphoric acid ester:
-Monoethyl phosphate, monobutyl phosphate, methyl acid phosphate, ethyl acid phosphate, butyl acid phosphate, dibutyl phosphate, trimethyl phosphate (TMP), triethyl phosphate (TEP), triphenylphosphine (TPP), tri Aromatic phosphates such as cresyl phosphate (TCP), trixylenyl phosphate (TXP), cresyldiphenyl phosphate (CDP), 2-ethylhexyldiphenyl phosphate (EHDP), derivative compounds thereof, and condensates thereof. ..
-A reaction product of phosphorus oxychloride with a divalent phenolic compound and phenol (or alkylphenol). For example, aromatic condensed phosphoric acid esters such as resorcinol bis-diphenyl phosphate, resorcinol bis-dixylenyl phosphate, bisphenol A bis-diphenyl phosphate, derivative compounds thereof, and condensates thereof.

2) Halogen-containing phosphate ester: tris (chloroethyl) phosphate, tris (chloropropyl) phosphate, tris (dichloropropyl) phosphate, tris (dibromopropyl) phosphate, bis (2,3-dibromopropyl) -2 , 3-Dichloropropyl phosphate, bis (chloropropyl) octyl phosphate, etc., their derivative compounds, and their condensates.

3) Phosphonate ester: dimethylvinylphosphonate, diethylvinylphosphonate, diphenylvinylphosphonate, diphenylvinylphosphine oxide and the like, derivative compounds thereof, and condensates thereof.

Examples of the halogen-free phosphoric acid ester include "JAMP-2", "JAMP-4P", "JP-501", "JP-502", "JP-504", and "DBP" manufactured by Johoku Chemical Co., Ltd. , "TPP", "TEP", "TPP", "TCP", "TXP", "CDP", "PX-110", "# 41", "CR-" manufactured by Daihachi Chemical Industry Co., Ltd. 733S ”,“ CR-741 ”,“ PX-200 ”,“ DAIGUARD-400 / 540/580/610 ”, as halogen-containing phosphate esters“ TMCPP ”,“ CRP ”,“ CR-900 ”,“ Commercially available products such as "CR-504L", "CR-570", and "DAIGUARD-540" can be used.

As the phosphonate ester, for example, commercially available products such as "V series" manufactured by Katayama Chemical Industry Co., Ltd. and "Non Nen 73" manufactured by Maruhishi Yuka Kogyo Co., Ltd. can be used.

<Light diffuser>
In the present invention, the (meth) acrylic resin composition contains a specific light diffusing agent, so that the milk has suitable optical properties and coloring properties for exhibiting appropriate light diffusivity as a signboard / lighting material. A semi-colored resin molded product can be obtained.
As the light diffusing agent, the resin molded product (B) can be produced by using the inorganic pigment (D) described later or the resin particles (F) described later.

<Inorganic pigment (D)>
The inorganic pigment (D) is one of the constituents of the resin molded product (A) of the present invention. Examples of the inorganic pigment (D) include barium sulfate, calcium carbonate, aluminum hydroxide, potassium aluminum silicate (mica), aluminum silicate (kaolin), titanium oxide, silicon dioxide, potassium fluoride, and magnesium silicate (talc). ), Inorganic compounds such as glass beads. Among these, titanium oxide is preferable from the viewpoint of exhibiting the flame retardant performance of the resin molded product.

As the inorganic pigment (D), a commercially available product may be used, or a known method may be used for production. Commercially available products include, for example, Titanium oxide manufactured by Ishihara Sangyo Co., Ltd.), ultrafine titanium oxide TTO series, high-purity titanium oxide (CR-EL, PT series), and rutile manufactured by Sakai Chemical Industry Co., Ltd. Type (SR-1 etc.) Anatas type (A-110 etc.), STT-65C-S manufactured by Titanium Industry Co., Ltd., Nanotech manufactured by CI Kasei Co., Ltd., etc. Be done. The average particle size of the commercially available inorganic pigment (D) is not particularly limited, but may be selected depending on the purpose for which the resin molded product is used. For example, as a commercially available inorganic pigment, a pigment having a thickness of 0.1 to 1.5 μm can be obtained. As the inorganic pigment (D), a commercially available pigment may be used as it is, or may be used after surface treatment by a known method, if necessary.

In the present invention, by setting the content of the inorganic pigment (D) with respect to 100 parts by mass of the (meth) acrylic polymer (P) to 0.001 part by mass or more and 0.35 part by mass or less, an appropriate diffusion rate A resin molded product having the above is obtained. Further, when the upper limit of the content of the inorganic pigment (D) is 0.35 parts by mass or less, the flame retardancy of the resin molded product can be maintained, which is preferable. When the lower limit of the content of the inorganic pigment (D) is 0.001 part by mass or more, it is preferable because an appropriate diffusivity can be imparted to the resin molded product, and when it is 0.05 part by mass or more, the resin molded product is further subjected to It is more preferable because it can impart a milky half-color tone, and 0.2 parts by mass or more is further preferable.

<Resin particles (F)>
The resin particles (F) are one of the constituent components of the resin molded product (B) of the present invention. Examples of the resin particles (F) include (meth) acrylic resin particles, styrene resin particles, MS resin (methacryl-styrene copolymer resin) particles, silicone resin particles, polyethylene resin particles, and polypropylene resin particles. , Resin particles such as polyester resin particles and polyamide resin particles. These can be used alone or in combination of two or more. Examples of the structure of the resin particles (F) include a graft polymer. Examples of the form of the resin particles (F) include powders, beads, pellets and liquids. In the present invention, (meth) acrylic resin particles and styrene-based resin particles are preferable as the resin particles (F) from the viewpoint of light diffusivity of the resin molded body (B). As such resin particles (F), a commercially available product may be used, or the resin particles (F) may be produced from a monomer by a known method. As commercially available products, for example, as (meth) acrylic resin particles, Mitsubishi Rayon Co., Ltd.'s Metabren series (W-341), Soken Kagaku Co., Ltd.'s Chemisnow MR-2G, MS-300X, Asahi Kasei Chemicals Co., Ltd. Examples include commercially available products such as the Delpet series (SRB215) manufactured by Co., Ltd. Examples of the styrene-based resin particles include particles derived from styrene-based monomers such as styrene, p-methylstyrene, p-chlorostyrene, chloromethylstyrene, and α-methylstyrene. These styrene resin particles may or may not be crosslinked. Specific examples include commercially available products such as the SX series (SX-130H, SX-200H, SX-350H) manufactured by Soken Chemical Co., Ltd. and the SBX series (SBX-6, SBX-8) manufactured by Sekisui Plastics Co., Ltd. Be done.

The dispersed state and the average particle size of the resin particles (F) in the resin molded product (B) are not particularly limited, and may be controlled according to a known method according to the purpose in which the resin molded product is used. Specifically, the average particle size is preferably 0.5 μm or more and 20 μm or less. When the lower limit of the average particle size of the resin particles (F) in the resin molded product is 0.5 μm or more, it is preferable from the viewpoint of improving the dispersibility of the resin particles (F) in the resin molded product. When the upper limit of the average particle size is 20 μm or less, it is preferable from the viewpoint of the appearance of the resin molded product. The average particle size of the resin particles (F) can be obtained by the same method as that for measuring the average particle size of the inorganic pigment (D).

By setting the content of the resin particles (F) with respect to 100 parts by mass of the (meth) acrylic polymer (P) to 0.1 parts by mass or more and 4.0 parts by mass or less, an appropriate diffusivity and milky half color can be obtained. A resin molded product having a color tone can be obtained. Further, when the upper limit of the content of the resin particles (F) is 4.0 parts by mass or less, it is preferable because the flame retardancy of the resin molded product can be maintained, and the lower limit of the content of the resin particles (F) is 0.1 mass. If it is more than a portion, it is preferable because an appropriate diffusivity can be imparted to the resin molded body, and if it is 1.5 parts by mass or more, it is more preferable because a milky half-color tone can be further imparted to the resin molded body.

<Manufacturing method of (meth) acrylic resin composition>
As a method for obtaining the (meth) acrylic resin composition, for example, the polymerizable composition (S2) in which the phosphorus atom-containing compound (C) is contained in the polymerizable monomer composition (S1) shown below is polymerized. Then, a method of obtaining a (meth) acrylic resin composition can be mentioned.

<Polymerizable monomer composition (S1)>
The polymerizable monomer composition (S1) is an embodiment of a raw material for obtaining a (meth) acrylic resin composition, and is a monomer (B) having methyl methacrylate and two or more vinyl groups. And 5.0% by mass or more of the (meth) acrylic polymer (P1) containing the repeating unit derived from methyl methacrylate as the main component with respect to the total mass of the polymerizable monomer composition (S1). The total amount of the polymerizable monomer composition (S1) is a methacrylic acid ester (M) having an aromatic hydrocarbon group or an alicyclic hydrocarbon group having 3 to 20 carbon atoms in a side chain and 40% by mass or less. It is a composition containing 5.0% by mass or more and 15.0% by mass or less with respect to the mass.
In the present invention, the polymerizable monomer composition (S1) contains the (meth) acrylic polymer (P1), whereby the polymerizable monomer composition (S1) and the polymerizable composition Since the substance (S2) becomes a viscous liquid (hereinafter referred to as “silap”), the polymerization time can be shortened and the productivity can be improved.

The content of the repeating unit derived from methyl methacrylate in the (meth) acrylic polymer (P1) is not particularly limited, but the homopolymer of methyl methacrylate and the (meth) acrylic polymer ( 90% by mass or more and less than 100% by mass of the repeating unit derived from methyl methacrylate and 0% by mass or less of the repeating unit derived from a monomer copolymerizable with methyl methacrylate with respect to the total mass of P1). At least one selected from (co) polymers containing.
As the monomer copolymerizable with methyl methacrylate, the same monomer as the above-mentioned "copolymerizable monomer" can be used.

Further, the polymerizable monomer composition (S1) has an aromatic hydrocarbon group or an alicyclic hydrocarbon group having 3 to 20 carbon atoms in the side chain as the (meth) acrylic acid ester (M). A resin obtained by containing a methacrylic acid ester (M1) and an acrylic acid ester (M2) having an aromatic hydrocarbon group or an alicyclic hydrocarbon group having 3 to 20 carbon atoms in a side chain for the reasons described above. The flame retardancy and weather resistance of the molded body can be improved.
The methacrylic acid ester (M1) is contained in an amount of 4.0% by mass or more and 14.0% by mass or less based on the total mass of the polymerizable monomer composition (S1), and the acrylic acid ester (M2) is used. By containing 1.0% by mass or more and 5.0% by mass or less with respect to the total mass of the polymerizable monomer composition (S1), the flame retardancy and weather resistance of the obtained resin molded product are improved. Can be

The content of methyl methacrylate contained in the polymerizable monomer composition (S1) is not particularly limited, but is methacrylic with respect to the total mass of the polymerizable monomer composition (S1). By containing 45.0% by mass or more and 90.0% by mass or less of methyl acid, the transparency and mechanical strength of the obtained resin molded product can be improved.

By containing the monomer (B) in the polymerizable monomer composition (S1), the flame retardancy of the obtained resin molded product can be improved. The content of the monomer (B) is not particularly limited, but the polymerizable monomer composition (S1) is based on the total mass of the polymerizable monomer composition (S1). , The monomer (B) can contain 0.05% by mass or more and 0.40% by mass or less.

The polymerizable composition (S2) contains 5.0 parts by mass or more and 35 parts by mass or less of the phosphorus atom-containing compound (C) with respect to 100 parts by mass of the polymerizable monomer composition (S1). , The heat resistance and flame retardancy of the obtained resin molded product are improved.

Further, in the present invention, the polymerizable composition (S2) has suitable optical properties and coloring properties for exhibiting appropriate light diffusivity as a signboard / lighting material by containing a specific light diffusing agent. It is possible to obtain a milky semi-colored resin molded product having. As the light diffusing agent, the above-mentioned inorganic pigment (D) or the above-mentioned resin particles (F) can be used.

The content of the inorganic pigment (D) or the resin particles (F) contained in the polymerizable composition (S2) is not particularly limited, but is 100 parts by mass of the polymerizable monomer composition (S1). On the other hand, by containing 0.001 part by mass or more and 0.35 part by mass or less of the inorganic pigment or 0.1 part by mass or more and 4.0 part by mass or less of the resin fine particles, an appropriate diffusivity and a milky half-color tone can be obtained. A resin molded product having the same can be obtained.

<Method for Producing Polymerizable Monomer Composition (S1)>
The polymerizable monomer composition (S1) can contain a (meth) acrylic polymer (P1) containing a repeating unit derived from methyl methacrylate as a main component in advance.

Specifically, the polymerizable monomer composition (S1) is
The polymerizable single amount contains methyl methacrylate, a monomer (B) having two or more vinyl groups, and a (meth) acrylic polymer (P1) containing the repeating unit derived from methyl methacrylate as main components. A methacrylate ester having 5% by mass or more and 40% by mass or less and an aromatic hydrocarbon group or an alicyclic hydrocarbon group having 3 to 20 carbon atoms in a side chain with respect to the total mass of the body composition (S1). M), a mixture containing 5.0% by mass or more and 15% by mass or less with respect to the total mass of the polymerizable monomer composition (S1) can be obtained.

By containing the (meth) acrylic polymer (P1), the polymerizable monomer composition (S1) and the polymerizable composition (S2) become a viscous liquid (hereinafter referred to as "silapp"). , The polymerization time can be shortened and the productivity can be improved.

Examples of the method for obtaining the above-mentioned syrup include the following two methods.

(Method 1) A method for dissolving a polymer (P1) in a monomer mixture containing methyl methacrylate, the methacrylate ester (M) and the monomer (B) (Method 2) Methyl methacrylate (MMA) A known radical polymerization initiator is added to a single product of MMA or a monomer mixture containing 90% by mass or more and less than 100% by mass of MMA and a monomer copolymerizable with MMA of more than 0% by mass and 10% by mass or less. Then, a part thereof is polymerized, and then at least one selected from the above-mentioned methacrylate ester (M), the above-mentioned monomer (B), methyl methacrylate and a monomer copolymerizable with MMA is added in a predetermined amount. How to add.

A radical polymerization initiator used when polymerizing the monomer mixture to obtain a syrup of the polymerizable composition (S2), and a (meth) acrylic resin obtained by polymerizing the polymerizable composition (S2). Examples of the radical polymerization initiator used in obtaining the composition include azo compounds such as 2,2'-azobis (isobutyronitrile) and 2,2'-azobis (2,4-dimethylvaleronitrile). And peroxides such as benzoyl peroxide and lauroyl peroxide. In the present invention, an accelerator such as amine or mercaptan can be used in combination with the radical polymerization initiator, if necessary.

The amount of the radical polymerization initiator added can be appropriately determined depending on the intended purpose, but is usually 0.01 part by mass or more and 0.5 part by mass with respect to 100 parts by mass of the monomer in the polymerizable composition (S2). It is as follows.

The polymerization temperature at the time of radical polymerization is usually set appropriately in the range of 10 to 150 ° C. depending on the type of radical polymerization initiator used. In addition, the polymerizable composition (X1) can be polymerized under multi-step temperature conditions, if necessary.

Examples of the radical polymerization method include a bulk polymerization method, a suspension polymerization method, an emulsion polymerization method and a dispersion polymerization method. Among these, the bulk polymerization method is preferable in terms of productivity, and the bulk polymerization method is used. Of these, the cast polymerization (casting polymerization) method is more preferable.

When the (meth) acrylic resin composition is obtained by the cast polymerization method, for example, the (meth) acrylic resin composition can be obtained by injecting the polymerizable composition (S2) into a mold and polymerizing the composition.

<Manufacturing method of resin molded product>
The method for producing the resin molded product of the present invention is not particularly limited, and is, for example, from two inorganic glass plates or metal plates (SUS plates) whose periphery is sealed with a gasket such as a resin tube and opposed to each other. A cell cast method in which the polymerizable composition (S2) is injected into a mold and heated, or a space sealed with two single-sided mirror-polished stainless steel endless belts and gaskets that proceed in the same direction at the same speed. A method of obtaining a resin molded product by a continuous casting method in which the polymerizable composition (S2) is continuously injected and heated from the upstream using the above as a template and continuously polymerized can be mentioned. The spacing between the voids of the mold is appropriately adjusted so as to obtain a resin plate having a desired thickness, but is generally 1 to 30 mm.

<Resin molded product>
The heat resistance of the resin molded product generally tends to decrease as the flame retardancy improves, which is a so-called trade-off relationship with the flame retardancy. That is, the resin molded product of the present invention is a resin molded product having a remarkable property of achieving both flame retardancy and heat resistance, which are contradictory properties.

Examples of the shape of the resin molded body include a plate-shaped molded body (resin plate). The thickness of the resin plate is generally 1 mm or more and 30 mm or less. When the casting method described above is used, the thickness (diameter) of the gasket can be appropriately adjusted to obtain a resin plate having a desired thickness.

Hereinafter, the present invention will be described with reference to examples. In the following, "parts" and "%" indicate "parts by mass" and "% by mass", respectively.

The abbreviations of the compounds used in Examples and Comparative Examples are as follows.
MMA: Methyl methacrylate IBXMA: Isobornyl methacrylate IBXA: Isobornyl acrylate EDMA: Ethylene glycol dimethacrylate CR570: Chlorine-containing condensed phosphoric acid ester (trade name, manufactured by Daihachi Chemical Industry Co., Ltd.)
St-based particles: Commercially available styrene-based resin particles (GPC weight average molecular weight (Mw): 91,000)
Titanium oxide: Commercially available titanium oxide (average particle size: 0.26 μm)

<Evaluation method>
Evaluation in Examples and Comparative Examples was carried out by the following method.
(1) Flame Retardant A test piece of a resin molded product was prepared in accordance with the flame resistance test A method of JIS K 6911-1979, and the time required for self-extinguishing the test piece (self-extinguishing time) was measured. In addition, the following four-grade evaluation was performed according to the self-extinguishing time, and when "◎" and "○", the flame retardancy was passed.
⊚: The self-extinguishing time of the test piece is less than 1 minute.
◯: The self-extinguishing time of the test piece is 1 minute or more and less than 3 minutes.
X: The self-extinguishing time of the test piece is 3 minutes or more.
XX: The test piece does not erase by itself.

(2) Heat resistance (HDT)
A test piece (length 127 mm x width 12.7 mm) of a resin molded body is prepared in accordance with JIS K 7191, and the deflection temperature under load (hereinafter referred to as "HDT") (° C.) of the test piece is measured and heat resistant. Sex was evaluated. The following three grades were evaluated according to the HDT, and the results were judged as "◎" and "○".
⊚: HDT exceeds 80 ° C.
〇: HDT is 70 ° C. or higher and lower than 80 ° C.
X: HDT is less than 70 ° C.

(3) Haze value The haze value of the test piece (thickness 5 mm) of the resin molded product was measured using a haze meter (manufactured by Nippon Denshoku Kogyo Co., Ltd., product: NDH 7000) in accordance with JIS K 7136. The following three grades were evaluated according to the haze value, and the results were judged as "◎" and "○".
⊚: The haze value is 2.0% or less.
〇: The haze value exceeds 2.0% and is 10.0% or less.
X: The haze value exceeds 10.0%.

(4) Quantification of residual monomer in the resin molded product The content of the residual monomer in the resin molded product is measured by a gas chromatography measuring device (GC device) (manufactured by Shimadzu Corporation, product name: gas chromatography GC2014, column used: frontier). Using DB-5 manufactured by Lab, outer diameter 0.25 mm / inner diameter 0.25 μm, length 30 m, detector: FID), the following was performed.
2.0 g of the resin molded product was dissolved in 30 ml of methylene chloride, and this was used as a sample for GC. 1.0 μl of a GC sample was injected into a GC apparatus, held at 60 ° C. for 2 minutes, and then heated to 150 ° C. at a heating rate of 15 ° C./min. The content of the monomers used in this experimental example and this comparative example was calculated based on the peak area of the obtained gas chromatogram and the calibration curve prepared in advance.

(5) Weather resistance According to JIS K7350-4, the resin molded product was exposed to 1000 hours with a sunshine weather meter (conditions: 63 ° C., 50%, water spray time 12 minutes / 60 minutes). The yellow index (YI) was measured before and after the exposure test, and the difference was defined as ΔYI. The following three-grade evaluation was performed according to the ΔYI value, and the results were judged as “◎” and “〇”.
⊚: ΔYI is 2 or less.
〇: ΔYI is more than 2 and 4 or less.
X: ΔYI exceeds 4.

(6) Diffusibility The following evaluation was performed using a plate-shaped resin molded product having a thickness of 3 mm. The resin molded body was installed at a distance of 1.5 m from the lit 45 W fluorescent lamp, and it was evaluated whether or not the lamp shape of the fluorescent lamp could be confirmed through the resin molded body.
◯: The lamp shape of the fluorescent lamp cannot be confirmed.
Δ: The lamp shape of the fluorescent lamp can be confirmed very slightly.
X: The lamp shape of the fluorescent lamp can be clearly confirmed.

(7) Diffusion rate The following evaluation was performed using a plate-shaped resin molded product having a thickness of 3 mm. Using a variable-angle photometer (manufactured by Murakami Color Technology Laboratory Co., Ltd., trade name: GP-200), when light is incident on the sample at 0 °, it is 5 °, 20 °, 70 ° with respect to the sample. The brightness value of the transmitted light at an angle was measured, and the diffusion rate was calculated.

(8) L *, a * and b *
The following evaluation was carried out using a plate-shaped resin molded product having a thickness of 3 mm. The spectral reflectance coefficient was measured using a self-recording spectrophotometer (manufactured by Hitachi, Ltd., trade name: U-4000), and L *, a * and b * were calculated.

(9) Evaluation of Resin Molded Product with Stretching Rate of 30% After heating a plate-shaped resin molded product with a thickness of 3 mm at 180 ° C. for 2 minutes, a vacuum forming machine has a vacuum degree of 760 mmHg, a molding temperature of 230 ° C., and a molding time of 30 seconds. Under the conditions of (1), the product was molded into a hat shape (cylindrical shape having a diameter of about 10 cm and a height of about 4 cm) to obtain a resin molded product test piece having a draw ratio of 30%. The following evaluation was performed using the obtained resin molded product test piece having a draw ratio of 30%.

(9-1) Translucency of Fluorescent Lamp The stretched surface of the resin molded body test piece was installed at a distance of 1.5 m from the lit 45 W fluorescent lamp, and the lamp shape of the fluorescent lamp was confirmed through the resin molded body test piece. We evaluated whether it could be done.
◯: The lamp shape of the fluorescent lamp cannot be confirmed.
Δ: The lamp shape of the fluorescent lamp can be confirmed very slightly.
X: The lamp shape of the fluorescent lamp can be clearly confirmed.

(9-2) The stretched surface of the transparent resin molded product test piece of the LED module is 10 cm from the LED module with lens (manufactured by First System Co., Ltd., emission color: neutral white, average color temperature: 6,300 ° K). It was installed at a distance and evaluated whether the shape of the LED module could be confirmed through the resin molded product test piece.
◯: The shape of the LED module of the LED module cannot be confirmed.
Δ: The shape of the LED module of the LED module can be confirmed very slightly.
X: The shape of the LED module of the LED module can be clearly confirmed.

(9-3) Clearness of the image of the fluorescent lamp The image is projected on the stretched surface of the resin molded body test piece when a lit 45 W fluorescent lamp is installed 1.5 m directly above the stretched surface of the resin molded body test piece. The clearness of the image of the fluorescent lamp was visually evaluated.
◯: The fluorescent lamp image is clearly shown.
Δ: The fluorescent lamp image is slightly grainy.
X: The fluorescent lamp image is large and rough.

Hereinafter, Examples 1 to 13 disclose an example of the (meth) acrylic resin composition and the resin molded product.
[Example 1]
(1) Production of Syrap (A) 100 parts by mass of MMA was supplied to a reactor (polymerization kettle) equipped with a cooling tube, a thermometer and a stirrer, and heating was started after bubbling with nitrogen gas while stirring. When the internal temperature reaches 60 ° C, 0.1 part of 2,2'-azobis- (2,4-dimethylvaleronitrile) as a radical polymerization initiator is added, and the mixture is further heated to an internal temperature of 100 ° C. , Held for 13 minutes. The reactor was then cooled to room temperature to give syrup (A) containing 30% by weight of polymethyl methacrylate and 70% by weight of MMA.

(2) Cast Polymerization The above syrup (A) 83.1 parts by mass, IBXMA 4.4 parts by mass as monomer (B), EDMA 0.15 parts by mass and CR570 as phosphorus atom-containing compound (C) (Daihachi Kagaku) 12.0 parts by mass of (trade name) manufactured by Kogyo Co., Ltd. was added, and 0.30 parts by mass of t-hexyl peroxypivalate was further added to obtain a polymerizable composition (S2). The two SUS plates were opposed to each other, and the peripheral edge between the SUS plates was sealed with a resin gasket, and the gap between the two SUS plates using this as a "mold" was 4.1 mm. Next, the polymerizable composition (S2) was poured into the mold and heated at 82 ° C. for 30 minutes and then at 130 ° C. for 30 minutes to polymerize the polymerizable composition (S2). Then, the mold after the completion of polymerization was cooled to room temperature, and the SUS plate was removed to obtain a plate-shaped resin molded product having a thickness of 3.0 mm.

A test piece for flame retardancy evaluation and a test piece for heat resistance evaluation were cut out from the obtained resin molded product using a cutting machine, and then the cut surface of the test piece was polished with a milling machine. Table 2 shows the evaluation results of the resin molded product. The flame retardancy of the obtained resin molded product was flame retardant according to the flame resistance test A method of JIS K 6911-1979, the heat resistance was 71 ° C., and the weather resistance (ΔYI) was good. Table 2 shows the evaluation results of the resin molded product.

[Examples 2 to 9]
A resin molded product was obtained in the same manner as in Example 1 except that the composition of the polymerizable composition (S2) was as shown in Table 1. In Examples 5 to 9, when various monomers such as IBXMA and the flame retardant (CR750) were added to the syrup (A), the light diffusing agents shown in Table 1 were added at the same time. Table 2 shows the evaluation results of the obtained resin molded product.
Further, as shown in Table 2, the resin molded products of Examples 5 to 9 had appropriate light diffusivity and milky half-color.

[Comparative Example 1]
Using the syrup (A) prepared in Example 1, a resin molded product was obtained in the same manner as in Example 1 except that the composition of the polymerizable composition (S2) was as shown in Table 2. The obtained resin molded product whose evaluation result of the resin molded product is shown in Table 2 was inferior in heat resistance because the content of the repeating unit derived from (meth) acrylic acid ester (M) was small.

[Comparative Example 2]
A resin molded product was obtained in the same manner as in Example 1 except that the composition of the polymerizable composition (S2) was as shown in Table 2. Table 2 shows the evaluation results of the obtained resin molded product. Since the obtained resin molded product contains an excessive amount of repeating units derived from methacrylic acid ester (M1) and does not contain repeating units derived from acrylic acid ester (M2), the amount of residual monomers in the obtained resin molded product The haze value was high and the weather resistance was inferior.

[Comparative Examples 3 to 6]
A resin molded product was obtained in the same manner as in Example 1 except that the composition of the polymerizable composition (S2) was as shown in Table 2 and the light diffusing agent shown in Table 2 was further used. Table 2 shows the evaluation results of the obtained resin molded product.

Since the resin molded product obtained in Comparative Example 3 does not contain a repeating unit derived from (meth) acrylic acid ester (M), it is difficult to compare with Examples 5 to 8 containing the same amount of the same light diffusing agent. The flammability was inferior.

Since the resin molded product obtained in Comparative Example 4 contains an excessive amount of repeating units derived from (meth) acrylic acid ester (M), it is compared with Examples 5 to 8 containing the same amount of the same light diffusing agent. It was inferior in flame retardancy and weather resistance.

Since the resin molded product obtained in Comparative Example 5 does not contain a repeating unit derived from (meth) acrylic acid ester (M), it is flame-retardant as compared with Example 9 containing the same amount of the same light diffusing agent. The sex was inferior.

Since the resin molded product obtained in Comparative Example 6 does not contain a repeating unit derived from (meth) acrylic acid ester (M2), it has weather resistance as compared with Example 9 containing the same amount of the same light diffusing agent. Was inferior.

INDUSTRIAL APPLICABILITY According to the present invention, a (meth) acrylic resin composition having good heat resistance and transparency and further high flame retardancy, and a resin molded product composed of the (meth) acrylic resin composition are stably provided. can do. Such a resin molded product can be suitably used for applications such as signboards that require high flame retardancy.

Claims (17)

A (meth) acrylic resin composition containing a (meth) acrylic polymer (P) and a phosphorus atom-containing compound (C).
The (meth) acrylic polymer (P) is
Repeating units derived from methyl methacrylate and
A repeating unit derived from a monomer (B) having two or more vinyl groups,
A repeating unit derived from a (meth) acrylic acid ester (M) having an aromatic hydrocarbon group or an alicyclic hydrocarbon group having 3 to 20 carbon atoms in a side chain of the (meth) acrylic polymer (P). A (meth) acrylic resin composition containing 5.0% by mass or more and 15% by mass or less with respect to the total mass.
The (meth) acrylic polymer (P) is used as a repeating unit derived from the (meth) acrylic acid ester (M).
A repeating unit derived from a methacrylic acid ester (M1) having an aromatic hydrocarbon group or an alicyclic hydrocarbon group having 3 to 20 carbon atoms in a side chain is added to the total mass of the (meth) acrylic polymer (P). On the other hand, 4.0% by mass or more and 14% by mass or less, and
A repeating unit derived from an acrylic acid ester (M2) having an aromatic hydrocarbon group or an alicyclic hydrocarbon group having 3 to 20 carbon atoms in a side chain is added to the total mass of the (meth) acrylic polymer (P). On the other hand, it contains 1.0% by mass or more and 5.0% by mass or less, and
The total of the repeating unit derived from the methacrylic acid ester (M1) and the repeating unit derived from the acrylic acid ester (M2) is 5.0% by mass or more with respect to the total mass of the (meth) acrylic polymer (P). 15% by mass or less,
A (meth) acrylic resin composition in which the phosphorus atom-containing compound (C) is at least one selected from a phosphoric acid ester and a phosphonic acid ester. The (meth) acrylic polymer (P) contains 81% by mass or more and 95% by mass or less of a repeating unit derived from methyl methacrylate with respect to the total mass of the (meth) acrylic polymer (P).
(Meth) acrylic resin composition according to claim 1. The total content of the repeating unit derived from the methacrylic acid ester (M1) and the repeating unit derived from the acrylic acid ester (M2) is 5.0% by mass or more and 11% by mass or less.
The (meth) acrylic resin composition according to claim 1 or 2. The methacrylic acid ester (M1) is at least one selected from isobornyl methacrylate and cyclohexyl methacrylate.
The (meth) acrylic resin composition according to any one of claims 1 to 3. The acrylic acid ester (M2) is at least one selected from isobornyl acrylate and cyclohexyl acrylate.
The (meth) acrylic resin composition according to any one of claims 1 to 4. The (meth) acrylic polymer (P) is 0.40% by mass or more of the repeating unit derived from the monomer (B) with respect to the total mass of the (meth) acrylic polymer (P). Including mass% or less,
The (meth) acrylic resin composition according to any one of claims 1 to 5. The monomer (B) is at least one selected from ethylene glycol di (meth) acrylate and neopentyl glycol di (meth) acrylate.
The (meth) acrylic resin composition according to any one of claims 1 to 6. The (meth) acrylic resin composition contains 5.0 parts by mass or more and 35 parts by mass of the phosphorus atom-containing compound (C) with respect to 100 parts by mass of the (meth) acrylic polymer (P).
The (meth) acrylic resin composition according to any one of claims 1 to 7. The methacrylic resin composition contains 0.001 part by mass or more and 0.35 part by mass or less of the inorganic pigment (D) with respect to 100 parts by mass of the (meth) acrylic polymer (P).
The (meth) acrylic resin composition according to any one of claims 1 to 8. The methacrylic resin composition contains 0.1 part by mass or more and 4.0 parts by mass or less of the resin fine particles (F) with respect to 100 parts by mass of the (meth) acrylic polymer (P).
The (meth) acrylic resin composition according to any one of claims 1 to 9. A resin molded product comprising the (meth) acrylic resin composition according to any one of claims 1 to 10. A method for producing a (meth) acrylic resin composition by polymerizing a polymerizable monomer composition (S1) and a polymerizable composition (S2) containing a phosphorus atom-containing compound (C).
The polymerizable monomer composition (S1)
With methyl methacrylate,
A monomer (B) having two or more vinyl groups and
The polymer (P1) containing a repeating unit derived from methyl methacrylate as a main component is 5.0% by mass or more and 40% by mass or less based on the total mass of the polymerizable monomer composition (S1).
A (meth) acrylic acid ester (M) having an aromatic hydrocarbon group or an alicyclic hydrocarbon group having 3 to 20 carbon atoms in a side chain is added to the total mass of the polymerizable monomer composition (S1). A method for producing a (meth) acrylic resin composition containing 5.0% by mass or more and 15% by mass or less.
The (meth) acrylic polymer (P1) is 90% by mass of a repeating unit derived from methyl methacrylate with respect to the total mass of the copolymer of methyl methacrylate and the (meth) acrylic polymer (P1). At least one selected from (co) polymers including the above,
The polymerizable monomer composition (S1) is used as the (meth) acrylic acid ester (M).
A methacrylate ester (M1) having an aromatic hydrocarbon group or an alicyclic hydrocarbon group having 3 to 20 carbon atoms in a side chain, and an aromatic hydrocarbon group or an alicyclic hydrocarbon group having 3 to 20 carbon atoms are used. Contains the acrylic acid ester (M2) on the side chain and
The methacrylic acid ester (M1) was added to the total mass of the polymerizable monomer composition (S1) by 4.0% by mass or more and 14.0% by mass or less, and the acrylic acid ester (M2) was added. It contains 1.0% by mass or more and 5.0% by mass or less with respect to the total mass of the polymerizable monomer composition (S1).
The phosphorus atom-containing compound (C) is at least one selected from a phosphoric acid ester and a phosphonic acid ester.
A method for producing a (meth) acrylic resin composition. The polymerizable monomer composition (S1) contains 45.0% by mass or more and 90.0% by mass or less of methyl methacrylate with respect to the total mass of the polymerizable monomer composition (S1).
The method for producing a (meth) acrylic resin composition according to claim 12 . The polymerizable monomer composition (S1) is 0.05% by mass or more and 0.40% by mass or less of the monomer (B) with respect to the total mass of the polymerizable monomer composition (S1). including,
The method for producing a (meth) acrylic resin composition according to claim 12 or 13. The polymerizable composition (S2) contains 5.0 parts by mass or more and 35 parts by mass of the phosphorus atom-containing compound (C) with respect to 100 parts by mass of the polymerizable monomer composition (S1).
The method for producing a (meth) acrylic resin composition according to any one of claims 12 to 14. The polymerizable composition (S2) contains 0.001 parts by mass or more and 0.35 parts by mass or less of an inorganic pigment with respect to 100 parts by mass of the polymerizable monomer composition (S1).
The method for producing a (meth) acrylic resin composition according to any one of claims 12 to 15. The polymerizable composition (S2) contains 0.1 part by mass or more and 4.0 parts by mass or less of resin fine particles with respect to 100 parts by mass of the polymerizable monomer composition (S1).
The method for producing a (meth) acrylic resin composition according to any one of claims 12 to 16.