JP4619902B2 - Optical article for secondary processing and secondary processed optical article - Google Patents

Description

  The present invention is a melt-molded composition comprising a specific multilayer structure polymer particle and a specific methacrylic resin, which is excellent in transparency and weather resistance. And a secondary processing optical article obtained by subjecting the optical article to heat bending.

  Optical articles made by melt-molding polymer materials such as polycarbonate, acrylic resin and polystyrene are significantly superior in impact resistance compared to glass, and also in other performance such as moldability and dyeability. Therefore, it is widely used. In particular, the demand for secondary processed articles obtained by subjecting these optical articles to partial melt molding has increased in recent years as substitutes for glass.

However, an optical article made of a polymer material excluding soft polyvinyl chloride has poor workability, and the curved surface portion after the secondary processing is reduced in impact resistance due to stress strain, and is not deformed or broken during the secondary processing. There is a problem that it is likely to occur. In addition, optical articles made of a polymer material excluding acrylic resins cannot generally be said to have good weather resistance. As means for solving these problems, a flexible optical article that can be bent at room temperature, which is obtained by melt-molding specific acrylic multilayered polymer particles, has been proposed (see Patent Document 1). With the diversification of uses of processed articles, the present situation is that further improvement of secondary processability in optical articles is required.
JP 2002-277601 A (Claims)

  An object of the present invention is a composition comprising a specific multilayer structure polymer particle and a specific methacrylic resin and excellent in transparency and weather resistance, without impairing the excellent transparency and weather resistance of the acrylic polymer material. Another object of the present invention is to provide an optical article for secondary processing in which the thickness change after bending is small and the bending portion is not broken and stretched, and a secondary processed optical article obtained by subjecting the optical article to heat bending.

  In order to solve the above problems, the present inventors have made various studies, and for secondary processing formed by melt-molding a composition satisfying specific requirements comprising specific multilayer structure polymer particles and methacrylic resin The inventors have found that optical articles exhibit excellent transparency, weather resistance, and secondary processability, and have completed the present invention.

That is, the present invention
An optical article for secondary processing having a minimum length of 5 mm or more of length, width and height obtained by melt-molding a composition comprising a multilayer structure polymer particle (A) and a methacrylic resin (B). The multilayer structure polymer particles (A) are
(1) It comprises two or more layers having at least one of the following rubber component layers (I) inside and at least one of the following thermoplastic resin component layers (II) at least on the outermost portion;
(2) The rubber component layer (I) is composed of 50 to 99.99% by mass of an acrylate ester, 49.99 to 0% by mass of another monofunctional monomer copolymerizable with the acrylate ester, and multifunctional. A polymer layer formed by copolymerization of a monomer mixture (i) comprising 0.01 to 10% by weight of monomers;
(3) The thermoplastic resin component layer (II) is a monomer (ii) comprising 40 to 100% by mass of a methacrylic acid ester and 60 to 0% by mass of another monomer copolymerizable with the methacrylic acid ester. A polymer layer formed by polymerization;
(4) For the polymer constituting the outermost layer of the thermoplastic resin component layer (II), the number average molecular weight measured by the GPC method is 30,000 or less;
(5) The ratio of the total mass of the rubber component layer (I) to the total mass of the thermoplastic resin component layer (II) is in the range of 30/70 to 90/10 in the layer (I) / layer (II). ;
(6) The average particle size is 150 nm or less; and (7) The refractive index n _d (I) of the copolymer constituting any one layer of the rubber component layer (I) and the thermoplastic resin component layer (II ) In any combination with the refractive index n _d (II) of the polymer constituting any one layer;
| N _d (I) −n _d (II) | <0.005
The composition is characterized by the following requirements (a) and (b):
Requirement (A) The mass ratio of the multilayer polymer particles (A) to the methacrylic resin (B) is 30:70 to 70:30;
In all combinations of the requirement (ii) the rubber component layer refractive index of the polymer constituting any one layer n _{d (I)} and the refractive index n _d of the methacrylic resin (B) of (I) _(B) The following relationship holds:
| N _d (I) −n _d (B) | <0.005
It is related with the optical article for secondary processing which satisfies these.

  The present invention also relates to a secondary processed optical article obtained by heating and bending the above optical article.

  According to the present invention, an optical article for secondary processing which has excellent transparency and weather resistance of an acrylic polymer material, has a small thickness reduction after bending, and does not cause break elongation at the bent portion, and the optical article. A secondary processed optical article obtained by heat bending is provided.

  Hereinafter, preferred embodiments of the present invention will be described, but the present invention is not limited to the following descriptions.

  The multilayer structure polymer particle (A) used in the present invention has at least one rubber component layer (I) and at least a thermoplastic resin component layer (II) as an outermost layer. The number of layers constituting the multilayer polymer particles (A) may be two or more, and may be composed of three layers or four or more layers. In the case of a two-layer structure, the structure is layer (I) (center layer) / layer (II) (outermost layer). In the case of a three-layer structure, layer (I) (innermost layer) / layer (I) ( Intermediate layer) / layer (II) (outermost layer), layer (I) (innermost layer) / layer (II) (intermediate layer) / layer (II) (outermost layer) or layer (II) (innermost layer) / layer (I) (intermediate layer) / layer (II) (outermost layer), and in the case of a four-layer structure, for example, layer (I) (innermost layer) / layer (II) (intermediate layer) / layer It can have a configuration of (I) (intermediate layer) / layer (II) (outermost layer). Among these, the layer (I) (center layer) / layer (II) (outermost layer) has a two-layer structure; or layer (I) (innermost layer) / layer (I) (intermediate layer) in terms of excellent handling properties. ) / Layer (II) (outermost layer) is preferred.

  Moreover, the total mass ratio of the layer (I) and the layer (II) is within the range of 30/70 to 90/10 in (I) / (II). If the ratio of the layer (I) is smaller than this range, the flexibility of the optical article for secondary processing becomes insufficient. Conversely, if the ratio of the layer (I) is larger than this range, it is difficult to form a layer structure in a complete form. As a result, the melt fluidity is extremely lowered, making it difficult to mold and knead with other components. The total mass ratio of layer (I) and layer (II) is preferably in the range of 50/50 to 90/10 in (I) / (II), and in the range of 60/40 to 80/20. More preferably. The total mass of the layer (I) is the mass of the layer (I) in the case where the layer (I) in the multilayer structure polymer particles (A) is only one layer, and the layer (I) is composed of two or more layers In some cases, it is the sum of the masses of those layers. Similarly, the total mass of the layer (II) is the mass of the layer (II) when the layer (II) in the multilayer polymer particle (A) is only one layer, and the layer (II) is two or more layers. Is the sum of the masses of those layers.

  The layer (I) of the multilayer structure polymer particle (A) used in the present invention is 50 to 99.99% by mass of an acrylate ester, preferably 55 to 99.9% by mass, and can be copolymerized with the acrylate ester. Monofunctional monomer of 49.99 to 0% by mass, preferably 44.9 to 0% by mass, and polyfunctional monomer 0.01 to 10% by mass, preferably 0.2 to 2% by mass. It is a polymer layer having rubber elasticity formed by copolymerization of the monomer mixture (i).

Specific examples of the acrylate used to form the layer (I) include methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, s-butyl acrylate, and t-butyl acrylate. , pentyl acrylate, hexyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, dodecyl acrylate, esters of acrylic acid and an aliphatic alcohol such as octadecyl acrylate, such as C ₁ ester of saturated aliphatic alcohols -C _18; cyclohexyl acrylate esters of acrylic acid and phenols phenyl acrylate; esters of cycloaliphatic alcohols acrylic acid with C ₅ or C ₆ benzyl acrylate les An ester of acrylic acid and an aromatic alcohol bets, and the like. The acrylate ester is a monomer mixture used to form the layer (I) (in the case where the multilayer polymer particle (A) has two or more layers (I), each layer (I)). In the range of 50 to 99.99% by mass with respect to i), these are used alone or in admixture of two or more. If the amount of the acrylate ester is less than 50% by mass, the rubber elasticity of the optical article for secondary processing will decrease, and if it exceeds 99.99% by mass, the structure of the multilayer polymer particles (A) is formed. Neither is preferred because it is not done.

  The polyfunctional monomer used to form the layer (I) is a monomer having two or more carbon-carbon double bonds in the molecule, such as acrylic acid, methacrylic acid, cinnamic acid, etc. Esters of unsaturated monocarboxylic acids with unsaturated alcohols such as allyl alcohol and methallyl alcohol; Diesters of the above unsaturated monocarboxylic acids with glycols such as ethylene glycol, butanediol, hexanediol; phthalic acid, terephthalic acid, Examples include esters of dicarboxylic acids such as isophthalic acid and maleic acid and the above-mentioned unsaturated alcohols. Specific examples include allyl acrylate, methallyl acrylate, allyl methacrylate, methallyl methacrylate, allyl cinnamate, and cinnamic acid. Methallyl, diallyl maleate, diallyl phthalate, diallyl terephthalate, diallyl isophthalate Divinylbenzene, ethylene glycol di (meth) acrylate, butanediol di (meth) acrylate, hexanediol di (meth) acrylate. Of these polyfunctional monomers, allyl methacrylate is particularly preferred. The “di (meth) acrylate” means a generic name of “diacrylate” and “dimethacrylate”. The polyfunctional monomer is a single amount used to form the layer (I) (in the case where the multilayer polymer particle (A) has two or more layers (I), each layer (I)). In the range of 0.01-10 mass% with respect to body mixture (i), it is used individually or in combination of 2 or more types. When the amount of the polyfunctional monomer is more than 10% by mass, the optical article for secondary processing does not exhibit rubber elasticity, and the flexibility becomes insufficient. Moreover, when the amount of the polyfunctional monomer is less than 0.01% by mass, the layer (I) is not formed as a particle structure, which is not preferable.

In order to form the layer (I), in addition to the acrylate ester and the polyfunctional monomer, another monofunctional monomer copolymerizable with the acrylate ester can be used in combination. Examples of the other monofunctional monomers include methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, pentyl methacrylate, hexyl methacrylate, octyl methacrylate, 2-ethylhexyl methacrylate, and dodecyl methacrylate. , Esters of methacrylic acid such as myristyl methacrylate, palmityl methacrylate, stearyl methacrylate, and behenyl methacrylate with aliphatic alcohols, for example, C ₁ -C ₂₂ saturated aliphatic alcohols; methacrylic acid such as cyclohexyl methacrylate and C ₅ or C ₆ Esters with alicyclic alcohols; Esters of methacrylic acid such as phenyl methacrylate with phenols, Ben Typical examples include methacrylic acid esters such as esters of methacrylic acid and aromatic alcohol such as methacrylic acid, but also styrene, α-methylstyrene, 1-vinylnaphthalene, 3-methylstyrene, 4-propylstyrene. , 4-cyclohexyl styrene, 4-dodecyl styrene, 2-ethyl-4-benzyl styrene, 4- (phenylbutyl) styrene, halogenated styrene and other aromatic vinyl monomers; acrylonitrile, methacrylonitrile, etc. cyanide Vinyl monomers; butadiene, isoprene, 2,3-dimethylbutadiene, 2-methyl-3-ethylbutadiene, 1,3-pentadiene, 3-methyl-1,3-pentadiene, 2-ethyl-1,3- Pentadiene, 1,3-hexadiene, 2-methyl-1,3-hexadiene, 3 Examples thereof include conjugated diene monomers such as 4-dimethyl-1,3-hexadiene, 1,3-heptadiene, 3-methyl-1,3-heptadiene, 1,3-octadiene, cyclopentadiene, chloroprene, and myrcene. . These monomers form layer (I) (when the multilayer polymer particle (A) has two or more layers (I), if necessary, each layer (I)). In the ratio of 49.99 mass% or less with respect to the monomer mixture (i) used for 1, it can use individually or in mixture of 2 or more types. When the proportion of the other monofunctional monomer exceeds 49.99% by mass, the weather resistance of the optical article for secondary processing becomes insufficient, which is not preferable.

  The layer (II) of the multilayer structure polymer particle (A) used in the present invention is 40 to 100% by weight, preferably 60 to 99% by weight, more preferably 80 to 99% by weight, and copolymerizable therewith. A polymer layer having thermoplasticity formed by polymerization of monomer (ii) consisting of 60 to 0% by mass, preferably 40 to 1% by mass, and more preferably 20 to 1% by mass. is there. When the amount of the methacrylic acid ester is less than 40% by mass, the weather resistance of the optical article for secondary processing becomes insufficient.

  Specific examples of the methacrylic acid ester used to form the layer (II) include methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, pentyl methacrylate, hexyl methacrylate, octyl methacrylate, Examples include 2-ethylhexyl methacrylate, cyclohexyl methacrylate, dodecyl methacrylate, myristyl methacrylate, palmityl methacrylate, stearyl methacrylate, behenyl methacrylate, octadecyl methacrylate, phenyl methacrylate, and benzyl methacrylate, and methyl methacrylate is preferable.

Specific examples of other copolymerizable monomers used to form layer (II) include methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, s-butyl. Esters of acrylic acid and aliphatic alcohols such as acrylate, t-butyl acrylate, pentyl acrylate, hexyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, dodecyl acrylate, octadecyl acrylate, etc., for example C ₁ -C ₁₈ saturated aliphatic alcohols; Esters of acrylic acid such as cyclohexyl acrylate and C ₅ or C ₆ alicyclic alcohols; styrene, α-methylstyrene, 1-vinylnaphthalene, 3-methylstyrene, 4-propyls Aromatic vinyl monomers such as tylene, 4-cyclohexylstyrene, 4-dodecylstyrene, 2-ethyl-4-benzylstyrene, 4- (phenylbutyl) styrene, halogenated styrene; cyan such as acrylonitrile and methacrylonitrile Vinylimide monomers; maleimide, N-methylmaleimide, N-ethylmaleimide, N-propylmaleimide, N-isopropylmaleimide, N-cyclohexylmaleimide, N-phenylmaleimide, N- (p-bromophenyl) maleimide, N -Maleimide monomers such as-(chlorophenyl) maleimide; and polyfunctional monomers shown in the above examples. Among these, acrylic acid alkyl esters such as methyl acrylate, ethyl acrylate, and n-butyl acrylate are preferable.

  The layer (I) is composed of a polymer component having rubber elasticity, and the layer (II) is composed of a polymer component having thermoplasticity. The conditions may be selected as appropriate.

  The multilayer polymer particles (A) used in the present invention have a GPC (gel permeation chromatography) method in which the number average molecular weight of the polymer constituting at least the outermost layer of the particles (II) contained therein is the GPC (gel permeation chromatography) method. It is important that it is 30,000 or less based on the measurement at. When the number average molecular weight exceeds 30,000, the flexibility in the optical article for secondary processing becomes insufficient, and the melt fluidity may be further lowered. The lower limit of the number average molecular weight is not necessarily strictly limited, but the number average molecular weight is preferably not less than 1,000 from the viewpoint of the passage of the multilayer structure polymer particle (A) in the production process. From the standpoint of compatibility between flexibility and permeability in the production process, it is particularly preferable that the number average molecular weight be in the range of 3,000 to 20,000.

  The average particle diameter of the multilayer structure polymer particles (A) used in the present invention is 150 nm or less. If it is larger than 150 nm, the flexibility becomes insufficient, and the melt fluidity may not be good. The lower limit of the average particle diameter is not particularly limited, but the average particle diameter is preferably 30 nm or more from the viewpoint of easily forming a predetermined layer structure of the multilayer structure polymer particles (A). The average particle diameter is more preferably 80 to 120 nm.

The multilayer structure polymer particle (A) used in the present invention is composed of the refractive index n _d (I) and the layer (II) of the copolymer constituting any one layer of the layer (I) contained therein. Types and masses of monomers constituting the monomer mixture forming each layer so as to satisfy the relationship of the following formula in all combinations with the refractive index n _d (II) of the polymer constituting any one layer It is necessary to select a fraction, and thereby, an optical article for secondary processing having extremely good transparency can be obtained.
| N _d (I) −n _d (II) | <0.005
The absolute value of n _d (I) −n _d (II) is particularly preferably 0.001 or less. When the absolute value of n _d (I) −n _d (II) is 0.005 or more, transparency in the optical article for secondary processing is lowered.

  The composition of the monomers forming the layer (I) and the layer (II) is that the layer (I) is composed of a polymer component having rubber elasticity, and the layer (II) is composed of a polymer component having thermoplasticity. As described above, the conditions may be appropriately selected within the range of the above-described types of monomers and usage ratios. Further, when the multilayer structure polymer particle (A) used in the present invention has three or more layers, at least two rubber component layers adjacent to each other and having different compositions constituting the layer (I) are rubber component layers. The refractive index of the outermost layer is formed so as to be intermediate between the refractive index of the rubber component layer adjacent to the inner side and the refractive index of the thermoplastic resin component layer adjacent to the outer side thereof. It is preferable from the viewpoint of transparency of the optical article for secondary processing that the type and amount of the monomer are different.

  The multilayer polymer particles (A) used in the present invention have a rubber component layer (Ia) in the innermost part in addition to the above-mentioned conditions from the viewpoint of physical properties and manufacturing simplicity, Multi-layer structure polymer particles having a three-layer structure having a rubber component layer (Ib) in an adjacent portion located so as to cover the outer surface and having a thermoplastic resin component layer (II) on the outermost portion are preferred.

  The layer (Ia) of the multilayer structure polymer particle (A) having a three-layer structure that can be used in the present invention is 50 to 99.99% by mass of an acrylate ester, preferably 55 to 99.9% by mass. Other monofunctional monomers copolymerizable with the ester 49.99-0% by mass, preferably 44.9-0% by mass, and polyfunctional monomers 0.01-10% by mass, preferably 0 It is a polymer layer having rubber elasticity formed by copolymerization of a monomer mixture (ia) comprising 1 to 2% by mass. The layer (Ib) is an acrylic ester of 50 to 99.99% by mass, preferably 55 to 99.9% by mass, and other monofunctional monomer 49.99 to copolymerizable with the acrylic ester. Copolymerization of monomer mixture (ib) comprising 0% by weight, preferably 44.9-0% by weight, and polyfunctional monomer 0.01-10% by weight, preferably 0.1-2% by weight It is the polymer layer which has the rubber elasticity formed by. In order to form the layers (Ia) and (Ib), the monomers used to form the layer (I) described above can be used.

  In the multilayer polymer particles (A) having a three-layer structure, the ratio between the sum of the masses of the rubber component layers (Ia) and (Ib) and the mass of the thermoplastic resin component layer (II) is [(Ia) + ( Ib)] / (II), it is within the range of 30/70 to 90/10. When the ratio of the sum of the masses of the layer (Ia) and the layer (Ib) is smaller than this range, the elastic recovery and flexibility in the optical article for secondary processing are insufficient, while the layers (Ia) and (Ib) If the ratio of the sum of the weights is larger than this range, it is difficult to form a layer structure in a complete form, and melt flowability is extremely reduced, so that kneading and melt molding with the methacrylic resin (B) become difficult. . In order to make the effect of the present invention more remarkable, the ratio of the sum of the masses of the rubber component layers (Ia) and (Ib) to the mass of the thermoplastic resin component layer (II) is [(Ia) + In (Ib)] / (II), it is preferably in the range of 50/50 to 90/10, and more preferably in the range of 60/40 to 80/20.

  In the multilayer polymer particles having a three-layer structure, the ratio of the mass of the rubber component layer (Ia) to the mass of the rubber component layer (Ib) is 5/95 to 95 in (Ia) / (Ib). / 5, preferably in the range of 20/80 to 80/20. When the ratio between the mass of the rubber component layer (Ia) and the mass of the rubber component layer (Ib) is outside the range of 5/95 to 95/5, generally, flexibility and other mechanical properties (such as tensile properties) It becomes difficult to achieve both.

  In the optical article for secondary processing of the present invention, in order to achieve both good flexibility and other mechanical properties, the layer (Ia) of the multilayer structure polymer particles (A) having a three-layer structure and For layer (Ib), it is important that the acrylic ester content (mass%) in the monomer mixture (ia) is higher than the acrylic ester content (mass%) in the monomer mixture (ib). is there. When the acrylic ester content (mass%) in the monomer mixture (ia) is equal to or less than the acrylic ester content (mass%) in the monomer mixture (ib) It is generally difficult to make good flexibility and other mechanical properties parallel to each other. For the purpose of making the effect of the present invention more remarkable, the content (mass%) of the acrylate ester in the monomer mixture (ia) and the content (mass%) of the acrylate ester in the monomer mixture (ib). %) [(Ia) (unit: mass%) − (ib) (unit: mass%)] may be a value of 3 mass% or more, preferably a value within the range of 4 to 30 mass%. desirable.

The multilayer structure polymer particle (A) having a three-layer structure has a refractive index n _d (Ia) of the copolymer constituting the rubber component layer (Ia) or a refractive index of the copolymer constituting the rubber component layer (Ib). The monomer mixture forming each layer is formed so that the relationship of the following formula is established between n _d (Ib) and the refractive index n _d (II) of the polymer constituting the thermoplastic resin component layer (II). By selecting the type and mass fraction of the constituting monomer, it is possible to obtain an optical article for secondary processing that has extremely good transparency.
| N _d (Ia) −n _d (II) | <0.005
| N _d (Ib) −n _d (II) | <0.005

  The multilayer structured polymer particles (A) used in the present invention are obtained by performing a polymerization reaction step for forming a rubber component layer and a polymerization reaction step for forming a thermoplastic resin component layer in a predetermined order. Having at least one rubber component layer (I) in the interior and forming at least one thermoplastic resin component layer (II) at least on the outermost surface, comprising sequentially forming layers from the portion toward the outside, 2 It can be produced according to a known production method for producing a multilayer structure polymer particle composed of two or more layers. However, it is necessary to pay attention to the following points.

(1) In the polymerization reaction step (a) for forming the rubber component layer (I), 50 to 99.99% by mass of an acrylate ester and another monofunctional monomer copolymerizable with the acrylate ester Copolymerizing a monomer mixture (i) comprising 49.99 to 0% by mass and 0.01 to 10% by mass of a polyfunctional monomer.
(2) In the polymerization reaction step (b) for forming the thermoplastic resin component layer (II), 40 to 100% by mass of the methacrylic acid ester and other monomers 60 to 0 copolymerizable with the methacrylic acid ester Polymerizing the monomer (ii) consisting of mass%.
(3) In the polymerization reaction step (b), at least in the polymerization reaction step for forming the outermost thermoplastic resin component layer (II), the molecular weight regulator is 0 with respect to the monomer (ii). The polymerization reaction should be carried out using a ratio in the range of 4 to 10% by mass.
(4) The refractive index n _d (I) of the copolymer constituting any one layer of the rubber component layer (I) and the polymer constituting any one layer of the thermoplastic resin component layer (II) The type and amount of the monomer constituting the monomer mixture are selected so that the relationship of the following formula is established in all combinations with the refractive index n _d (II).
| N _d (I) −n _d (II) | <0.005
(5) The ratio of the total mass of the monomer mixture (i) and the total mass of the monomer (ii) used in the entire polymerization reaction step is as follows: monomer mixture (i) / monomer (ii) Within the range of 30/70 to 90/10.
(6) Control so that the average particle diameter of the multilayer structure polymer particles (A) at the time when all the polymerization reaction steps are completed is 150 nm or less.

  There is no particular limitation on the polymerization method for producing the multilayer structure polymer particles (A) used in the present invention. For example, according to a known polymerization method for producing ordinary multilayer structure polymer particles, A combination method, suspension polymerization method, solution polymerization method, or a combination thereof can be employed.

  For example, in emulsion polymerization, the multilayer polymer particles (A) used in the present invention can be obtained by performing polymerization for forming each layer in accordance with a known means. The temperature of emulsion polymerization is not necessarily limited, but a general range is 0 to 100 ° C. Examples of the emulsifier used herein include alkali metal salts of fatty acids such as sodium oleate, sodium laurate, and sodium stearate; sulfates of fatty alcohols such as sodium lauryl sulfate; rosinates such as potassium rosinate; dodecylbenzene Examples thereof include alkylaryl sulfonic acids such as sulfonic acids; phosphoric esters such as aromatic or aliphatic phosphoric monoesters and phosphoric diesters, and these are used in a combination of one kind or two or more kinds. As a polymerization initiator used in emulsion polymerization, a radical polymerization initiator is generally used. As specific examples of the radical polymerization initiator, peroxides such as persulfate, azobisisobutyronitrile, and benzoyl peroxide can be used alone. In addition, as a radical polymerization initiator, a redox initiator using a combination of organic hydroperoxides such as cumene hydroperoxide, diisopropylbenzene hydroperoxide, paramentane hydroperoxide and a reducing agent such as a transition metal salt is used. can do.

  As described above, by sequentially polymerizing a predetermined amount of a predetermined monomer mixture according to a known emulsion polymerization method, a predetermined polymer layer can be formed stepwise from the center of the particle toward the outside. However, in order to produce the multilayer polymer particles (A) used in the present invention, at least in the polymerization reaction step for forming the outermost layer, the molecular weight regulator is used in the monomer (ii) used in the step. It is particularly important to use it in a proportion within the range of 0.4 to 10% by mass. When producing ordinary multilayer structure polymer particles, the amount of the molecular weight regulator used in the polymerization reaction for forming the outermost thermoplastic resin component layer is generally from 0 to 0.00. Although it is about 3% by mass, when it is less than 0.4% by mass in this way, the number average molecular weight of the thermoplastic resin component constituting the layer becomes too high, and the flexibility of the optical article for secondary processing is increased. In some cases, the molding fluidity may be insufficient. For the purposes of the present invention, it is sufficient that the amount of the molecular weight regulator is at most 10% by mass based on the above criteria, and even if the amount higher than that is used, there is no further improvement in the flexibility-imparting effect. Since the residual amount of the molecular weight modifier in the structural polymer particles (A) increases, it is not desirable. The molecular weight regulator is preferably used in an amount of 0.4 to 5% by mass, more preferably 0.6 to 2% by mass with respect to the monomer (ii).

  Specific examples of molecular weight regulators include mercaptans such as n-octyl mercaptan, t-octyl mercaptan, n-dodecyl mercaptan, t-dodecyl mercaptan, mercaptoethanol; terpinolene, dipentene, t-terpinene and a small amount of other cyclic compounds. A terpene mixture composed of terpenes; halogenated hydrocarbons such as chloroform and carbon tetrachloride. Among these, alkyl mercaptans such as n-octyl mercaptan are preferable.

  Since the average particle size of the multilayer polymer particles (A) obtained by emulsion polymerization is affected by the polymerization conditions such as the amount of emulsifier added, the final multilayer structure weight can be easily selected by appropriately selecting these conditions. The average particle diameter of the coalesced particles (A) can be controlled to 150 nm or less.

  After emulsion polymerization, separation and acquisition of the produced multilayer structure polymer particles (A) from the polymerization reaction system can also be performed according to known methods, for example, acid precipitation method, salting out method, spray drying method, freeze coagulation method. Etc. can be adopted. In addition, the multilayer structure polymer particles (A) obtained by separation may be partially fused with each other in the outermost layer made of the thermoplastic resin component.

  The methacrylic resin (B) used in the present invention has 60 to 99.9% by mass of a methyl methacrylate unit and a copolymerizable copolymer from the viewpoint of ensuring excellent transparency and weather resistance, which are features of the methacrylic resin (B). It is preferably composed of 0.1 to 40% by mass of body units, 70 to 99.9% by mass of methyl methacrylate units and 0.1 to 30% by mass of monomer units copolymerizable therewith. More preferably, it is 80 to 99.9% by mass of methyl methacrylate units and 0.1 to 20% by mass of monomer units copolymerizable therewith.

  Examples of monomers copolymerizable with methyl methacrylate include methyl acrylate, ethyl acrylate, butyl acrylate, propyl acrylate, hexyl acrylate, cyclohexyl acrylate, 2-ethylhexyl acrylate, and acrylic acid. Acrylic acid ester monomers such as phenyl and benzyl acrylate; ethyl methacrylate, butyl methacrylate, propyl methacrylate, hexyl methacrylate, cyclohexyl methacrylate, phenyl methacrylate, methacrylic acid other than methyl methacrylate such as benzyl methacrylate Ester monomer; Vinyl acetate; Aromatic vinyl monomers such as styrene, p-methylstyrene, o-methylstyrene, m-methylstyrene, α-methylstyrene, vinylnaphthalene; Acrylonitrile, methacrylonitrile, etc. Nitriles; α, β-unsaturated carboxylic acids such as acrylic acid, methacrylic acid, and crotonic acid; maleimide compounds such as N-ethylmaleimide and N-cyclohexylmaleimide; and the like. These may be used alone or in combination of two or more. can do.

  The methacrylic resin (B) used in the present invention can be produced by a known method such as bulk polymerization, solution polymerization or suspension polymerization.

The multilayer structure polymer particles (A) and the methacrylic resin (B) used in the present invention have the following requirements (A) and (B):
Requirement (I) The mass ratio of the multilayer structure polymer particles (A) and the methacrylic resin (B) is 30:70 to 70:30, preferably 40:60 to 70:30;
In all combinations of the requirement (ii) the rubber component layer refractive index of the polymer constituting any one layer n _{d (I)} and the refractive index n _d of the methacrylic resin (B) of (I) _(B) The following formula:
_{| N d (I) -n d} (B) | <0.005,
Preferably | n _d (I) −n _d (B) | <0.003,
Or when the multilayer polymer particle (A) has a three-layer structure, the refractive index n _d (Ib) of the polymer constituting the rubber component layer (Ib) and the methacrylic resin (B ) And the refractive index n _d (B):
| N _d (Ib) −n _d (B) | <0.005,
Preferably | n _d (Ib) −n _d (B) | <0.003,
It is necessary that this relationship holds. When the multilayer structure polymer particles (A) and the methacrylic resin (B) satisfy these requirements, excellent transparency and secondary processability can be imparted to the optical article for secondary processing.

  In the optical article for secondary processing of the present invention, one or more physical property improving agents for improving physical properties may be blended during melt molding within a range not impairing the effects of the present invention. Such physical property improving agents are not particularly limited. For example, rubber, lubricant, antioxidant, plasticizer, light stabilizer, colorant, antistatic agent, flame retardant, filler (fiber reinforcing agent such as glass fiber, inorganic Etc.).

  Examples of the rubber include acrylic rubber; silicone rubber; styrene TPE (thermoplastic elastomer) such as SEPS, SEBS, and SIS; olefin rubber such as IR, EPR, and EPDM. As the lubricant, for example, stearic acid, behenic acid, stearoamic acid, methylene bisstearamide, hydroxystearic acid triglyceride, paraffin wax, ketone wax, octyl alcohol, hydrogenated oil and the like can be used. Examples of the antioxidant include 2,6-di-t-butyl-4-methylphenol, stearyl-β- (3,5-di-t-butyl-4-hydroxyphenyl) propionate, triethylene glycol-bis- Phenol compounds such as 3- (3-t-butyl-4-hydroxy-5-methylphenyl) propionate; amine compounds such as N, N-di-2-naphthyl-p-phenylenediamine may be used. it can. Examples of the plasticizer include phthalic acid esters such as di-2-ethylhexyl phthalate and dibutyl phthalate; phosphoric acid esters; adipic acid esters; polyethylene glycol and the like. Examples of the light stabilizer include pt-butylphenyl salicylate, 2,2′-dihydroxy-4-methoxybenzophenone, 2- (2-hydroxy-4-n-octoxyphenyl) benzotriazole, and the like. be able to. As the colorant, for example, titanium oxide, carbon black, other inorganic and organic pigments, and the like can be used. As the antistatic agent, for example, stearoamidopropyldimethyl-β-hydroxyethylammonium nitrate can be used. Examples of the flame retardant include organic halogen flame retardants such as tetrabromobisphenol A, decabromodiphenyl oxide, and brominated polycarbonate; non-halogen flame retardants such as antimony oxide, aluminum hydroxide, zinc borate, and tricresyl phosphate. A flame retardant etc. can be used.

  From the viewpoint of transparency, the optical article for secondary processing of the present invention preferably has a total light transmittance of 85% or more, more preferably 88% or more, measured according to JIS K7105. An optical article obtained by processing the article for secondary processing is preferably used in an application in which light is incident on a long light path from a light source located on an end surface of the rod-shaped article and light is emitted in the lateral direction of the rod-shaped article. The In order to effectively emit light in the lateral direction in such a usage pattern, the optical article for secondary processing of the present invention has a roughened light emitting surface within a range in which the total light transmittance is not reduced. Or a light diffusing means such as addition of a light diffusing agent can be added. Among these light diffusing means, for example, a light diffusing agent having an average particle diameter of 1 to 20 μm with an inorganic or synthetic resin type is used in an addition amount of 1% by mass or less with respect to the article for secondary processing. Can do. When the light diffusing agent is a synthetic resin system, the absolute value of the difference between the refractive index of the secondary processing optical article to which no light diffusing agent is added and the refractive index of the added light diffusing agent is, for example, 0.01. It can be about -0.2.

From the viewpoint of secondary processability, the optical article for secondary processing of the present invention has a storage elastic modulus of dynamic viscoelasticity at 0 ° C. of 6 × 10 ⁸ to 2 × 10 ⁹ Pa and dynamics at 100 ° C. The storage elastic modulus of the dynamic viscoelasticity is preferably 5 × 10 ^{7 to} 5 × 10 ⁸ Pa, the storage elastic modulus of the dynamic viscoelasticity at 0 ° C. is 7 × 10 ⁸ to 1 × 10 ⁹ Pa, and more preferably, the storage elastic modulus of dynamic viscoelasticity at 100 ° C. is ^{1 × 10 8 ~5 × 10 8} Pa.

  The optical article for secondary processing of the present invention is a mixture of multilayer polymer particles (A), a methacrylic resin (B), and, if necessary, a composition comprising one or more physical property improvers. Alternatively, it can be obtained by melt molding after kneading.

  The mixing and / or kneading method of the composition for obtaining the optical article for secondary processing of the present invention is not particularly limited. For example, mixing is performed using a tumbler, mixer, blender, etc., kneading is performed using a screw extruder, roll, or the like. Can be done. Moreover, there is no restriction | limiting in particular also about the melt molding method of the composition for obtaining the optical article for secondary processing of this invention, For example, molding methods, such as extrusion molding, injection molding, and compression molding, can be mentioned.

  As for the size of the optical article for secondary processing of the present invention, the minimum length among the length, width and height is 5 mm or more, and preferably 6 mm or more. If the minimum length among the vertical, horizontal, and height is less than 5 mm, the features of the present invention are not effectively exhibited. The optical article for secondary processing of the present invention has a relatively simple shape such as a plate shape, a sheet shape, a pipe shape, a rectangular parallelepiped shape, a cylindrical shape, a prismatic shape, a rod shape, etc., depending on the molding conditions employed. .

  The optical article for secondary processing of the present invention can be made into a secondary processed article having a more complicated shape by further performing secondary processing, that is, partial melt molding. The secondary processing is not particularly limited as long as it includes at least a heat bending process, and an adhesive process or the like may be further performed. Examples of the secondary processed article of the present invention include a neon sign-shaped display device, an LED light guide, an advertisement display signboard, a road sign, a housing and a cover of an illuminated game machine, and a decoration key chain.

  Hereinafter, the present invention will be specifically described with reference examples, examples and comparative examples, but the present invention is not limited thereto. In addition, the measurement of the physical-property value in a reference example, an Example, and a comparative example, calculation, and evaluation were performed with the following method.

(1) Refractive index The refractive index of each layer of the multilayer polymer particles (A) and the refractive index of the methacrylic resin (B) are homopolymers at 20 ° C. or 23 ° C. from “POLYMER HANDBOOK” (Wiley Interscience). The refractive index (polymethyl methacrylate 1.4893, poly n-butyl acrylate 1.466, polystyrene 1.59, polymethyl acrylate 1.472, etc.) was quoted and calculated according to the addition rule depending on the copolymer composition.

(2) Number average molecular weight The number average molecular weight of the polymer component constituting the outermost layer of the multilayer structure polymer particle (A) was sufficiently stirred in toluene at room temperature in a sample of the multilayer structure polymer particle (A). Thereafter, the solution obtained by centrifugation was measured by the GPC method, and the number average molecular weight obtained by this was regarded as the number average molecular weight of the polymer component constituting the outermost layer in the present invention.

(3) Average particle diameter The average particle diameter of the multilayer polymer particles (A) is determined using a laser particle size analyzer PAR-III (manufactured by Otsuka Electronics Co., Ltd.) using a sample collected from the latex after completion of polymerization. It was measured by the dynamic light scattering method and analyzed and determined by the cumulant method.

(4) Total light transmittance The total light transmittance of the optical article for secondary processing was measured with a test piece having a thickness of 3 mm according to JIS K7105.

(5) Storage elastic modulus The storage elastic modulus of dynamic viscoelasticity at 100 ° C. of the optical article for secondary processing is a longitudinal vibration type dynamic viscoelasticity measuring device Rheogel-E4000 for a sheet-like measurement sample having a thickness of 2 mm. (Manufactured by UBM) was measured under the conditions of a frequency of 1 Hz, an amplitude of 3 μm, a heating rate of 5 ° C./min, and an ambient temperature range of −50 ° C. to 200 ° C.

(6) Secondary workability About a sample for measurement of an optical article for secondary processing (a sheet-like material having a length of 200 mm x a width of 20 mm x a thickness of 10 mm), using a rod heater, a heating temperature of 100 ° C and a contact pressure of 0.5 MPa The contact heating was performed under the condition of a contact time of 5 minutes. Immediately thereafter, a stress of 0.5 MPa was applied to the bar heater contact portion of the sample, bending was performed at 90 °, and the sample was allowed to cool in a 23 ° C. atmosphere with no load for 1 minute. For the bent part of the obtained bent product, the thickness [t1 (mm)] is measured to calculate the decrease in thickness of the bent part [10-t1 (mm)], and the presence or absence of break extension is visually observed. The secondary processability of the optical article for subsequent processing was evaluated according to the following evaluation criteria.
(Double-circle): The thickness reduction of a bending part is less than 2 mm, and there is no breaking extension of a bending part (secondary workability is especially favorable).
○: The thickness reduction of the bent portion is less than 4 mm, and the bent portion is not stretched at break (secondary workability is good).
X: The thickness reduction | decrease of a bending part is 4 mm or more, or there exists break extension of a bending part (secondary workability is unsatisfactory).

  The multilayer structure polymer particle (A) used for this invention is demonstrated.

Reference Example 1 Production of multi-layer structure polymer particles (A-1) In a nitrogen atmosphere, 150 parts by mass of distilled water and Emar 20C (manufactured by Kao Corporation) as a polymerizer equipped with a stirring blade, a cooling tube, and a dropping funnel ) 1.0 part by mass and 1.0 part by mass of Poise 520 (manufactured by Kao Corporation) were added and heated to 80 ° C. to dissolve uniformly. Next, at the same temperature, 0.07 parts by mass of potassium peroxodisulfate was added, and then 54.6 parts by mass of n-butyl acrylate, 2.8 parts by mass of methyl methacrylate, 12.32 parts by mass of styrene, 0.28 parts of allyl methacrylate. A mixture of 0.35 parts by mass of phosphanol RA-600 (manufactured by Toho Chemical Co., Ltd.) was added dropwise over 60 minutes to form a first layer. After completion of the dropwise addition, the reaction was continued for another 60 minutes at 80 ° C., and it was confirmed by gas chromatography that each monomer was consumed by 99% or more.

  Next, 0.03 parts by mass of potassium peroxodisulfate was added to the obtained copolymer latex, followed by 28.5 parts by mass of methyl methacrylate, 1.5 parts by mass of methyl acrylate, and 0.3 parts by mass of n-octyl mercaptan. Was dropped from the dropping funnel over 30 minutes. After completion of the dropwise addition, the reaction was continued for an additional 60 minutes at 80 ° C., and the polymerization was completed by confirming that the monomer was consumed by gas chromatography. The average particle diameter of the multilayer structure polymer particles in the obtained latex was 95 nm. Further, the difference in refractive index between the first layer and the second layer of the multilayer structure polymer particles was 0.0005.

  The latex was agglomerated by cooling to −20 ° C. for 24 hours, and then the agglomerate was taken out and washed three times with hot water at 80 ° C. It dried under reduced pressure at 50 degreeC for 2 days, and obtained the aggregated-powder type two-layer type multilayer structure polymer particle (A-1). Table 1 shows the measurement results obtained for the multilayer structure polymer particles (A-1).

Reference Example 2 Production of multi-layer polymer particles (A-2) In a nitrogen atmosphere, 150 parts by mass of distilled water and Emar 20C (manufactured by Kao Corporation) as an emulsifier in a polymerization vessel equipped with a stirring blade, a cooling tube and a dropping funnel 1.0 part by mass and 1.0 part by mass of Poise 520 (manufactured by Kao Corporation) were added, and the mixture was heated to 80 ° C. and uniformly dissolved. Next, at the same temperature, after adding 0.05 parts by mass of potassium peroxodisulfate, 39 parts by mass of n-butyl acrylate, 1.5 parts by mass of methyl methacrylate, 9.3 parts by mass of styrene, 0.2 parts by mass of allyl methacrylate , And Phosphanol RA-600 (manufactured by Toho Chemical Co., Ltd.) 0.25 parts by mass was dropped over 60 minutes to form the first layer. After completion of the dropwise addition, the reaction was continued for another 60 minutes at 80 ° C., and it was confirmed by gas chromatography that each monomer was consumed by 99% or more.

  Next, at 80 ° C., 0.025 part by mass of potassium peroxodisulfate was added to the obtained copolymer latex, and then 18.5 parts by mass of n-butyl acrylate, 2.15 parts by mass of methyl methacrylate, 4.25 parts of styrene. A mixture consisting of 0.1 part by mass, 0.1 part by mass of allyl methacrylate, and 0.125 part by mass of phosphanol RA-600 (manufactured by Toho Chemical Co., Ltd .: surfactant) was added dropwise from the dropping funnel over 30 minutes, and the second layer Formed. After completion of the dropwise addition, the reaction was continued at 80 ° C. for a further 60 minutes, and it was confirmed by gas chromatography that the monomer had been consumed.

  Next, at 80 ° C., 0.025 part by mass of potassium peroxodisulfate was added to the obtained copolymer latex, and then 23.75 parts by mass of methyl methacrylate, 1.25 parts by mass of methyl acrylate, and n-octyl mercaptan 0 were added. .25 parts by mass was added dropwise from the dropping funnel over 1 hour. After completion of the dropwise addition, the reaction was continued at 80 ° C. for another 30 minutes, and it was confirmed by gas chromatography that the monomer had been consumed, and the polymerization was completed. The average particle diameter of the multilayer structure polymer particles in the obtained latex was 100 nm. The difference in refractive index between the first and third layers of the multilayer polymer particles was 0.0015, and the difference in refractive index between the second and third layers was 0.0009.

  The latex was agglomerated by cooling at −20 ° C. for 24 hours, and then the agglomerate was taken out and washed with hot water at 80 ° C. three times. It dried under reduced pressure at 50 degreeC for 2 days, and obtained the agglomerated powder-like two-layer type multilayer structure polymer particle (A-2). Table 1 shows the measurement results obtained for the multilayer structure polymer particles (A-2).

Reference Example 3 Production of multi-layer polymer particles (A-3) In a nitrogen atmosphere, 150 parts by mass of distilled water and Emar 20C (manufactured by Kao Corporation) as an emulsifier in a polymerization vessel equipped with a stirring blade, a cooling tube and a dropping funnel. 1.0 part by mass and 1.0 part by mass of Poise 520 (manufactured by Kao Corporation) were added, and the mixture was heated to 80 ° C. and uniformly dissolved. Next, at the same temperature, 0.045 parts by mass of potassium peroxodisulfate was added, and then 36.45 parts by mass of n-butyl acrylate, 8.325 parts by mass of styrene, 0.225 parts by mass of allyl methacrylate, and phosphanol RA- A mixture consisting of 0.225 parts by mass of 600 (manufactured by Toho Chemical Co., Ltd.) was dropped over 60 minutes to form the first layer. After completion of the dropwise addition, the reaction was continued for another 60 minutes at 80 ° C., and it was confirmed by gas chromatography that each monomer was consumed by 99% or more.

  Next, at 80 ° C., 0.025 parts by mass of potassium peroxodisulfate was added to the obtained copolymer latex, followed by 19.25 parts by mass of n-butyl acrylate, 1 part by mass of methyl methacrylate, and 4.625 parts by mass of styrene. , 0.125 parts by weight of allyl methacrylate, and 0.125 parts by weight of phosphanol RA-600 (manufactured by Toho Chemical Co., Ltd .: surfactant) are dropped from the dropping funnel over 30 minutes to form the second layer. did. After completion of the dropwise addition, the reaction was continued at 80 ° C. for a further 60 minutes, and it was confirmed by gas chromatography that the monomer had been consumed.

  Next, at 80 ° C., 0.025 parts by mass of potassium peroxodisulfate was added to the obtained copolymer latex, and then 28.5 parts by mass of methyl methacrylate, 1.5 parts by mass of methyl acrylate, and 0.2% of n-octyl mercaptan. 3 mass parts was dripped over 1 hour from the dropping funnel. After completion of the dropwise addition, the reaction was continued at 80 ° C. for another 30 minutes, and it was confirmed by gas chromatography that the monomer had been consumed, and the polymerization was completed. The average particle diameter of the multilayer structure polymer particles in the obtained latex was 105 nm. The difference in refractive index between the first and third layers of the multilayer structure polymer particles was 0.0008, and the difference in refractive index between the second and third layers was 0.0017.

  The latex was agglomerated by cooling to −20 ° C. for 24 hours, and then the agglomerate was taken out and washed three times with hot water at 80 ° C. It dried under reduced pressure at 50 degreeC for 2 days, and obtained the aggregated-powder type two-layer type multilayer structure polymer particle (A-3). Table 1 shows the measurement results obtained for the multilayer structure polymer particles (A-3).

Reference Example 4 Production of Multilayer Structure Polymer Particle (4) In a polymer atmosphere equipped with a stirring blade, a condenser tube and a dropping funnel under a nitrogen atmosphere, 150 parts by mass of distilled water and EMAL 20C (manufactured by Kao Corporation) as an emulsifier 0 parts by mass and 1.0 part by mass of Poise 520 (manufactured by Kao Corporation) were added, and the mixture was heated to 80 ° C. and uniformly dissolved. Next, at the same temperature, after adding 0.07 parts by mass of potassium peroxodisulfate, 69.65 parts by mass of n-butyl acrylate, 0.35 parts by mass of allyl methacrylate, and phosphanol RA-600 (manufactured by Toho Chemical Co., Ltd.) ) A mixture of 0.35 parts by mass was added dropwise over 60 minutes to form the first layer. After completion of the dropwise addition, the reaction was continued for another 60 minutes at 80 ° C., and it was confirmed by gas chromatography that each monomer was consumed by 99% or more.

  Next, 0.03 parts by mass of potassium peroxodisulfate was added to the obtained copolymer latex, followed by 28.5 parts by mass of methyl methacrylate, 1.5 parts by mass of methyl acrylate, and 0.3 parts by mass of n-octyl mercaptan. Was dropped from the dropping funnel over 30 minutes. After completion of the dropwise addition, the reaction was continued for an additional 60 minutes at 80 ° C., and the polymerization was completed by confirming that the monomer was consumed by gas chromatography. The average particle diameter of the multilayer structure polymer particles in the obtained latex was 100 nm. The difference in refractive index between the first layer and the second layer of the multilayer structure polymer particles was 0.0222.

  The latex was agglomerated by cooling to −20 ° C. for 24 hours, and then the agglomerate was taken out and washed three times with hot water at 80 ° C. It dried under reduced pressure at 50 degreeC for 2 days, and obtained the aggregated powder-form two-layer type multilayer structure polymer particle (4). The measurement results obtained for the multilayer structure polymer particles (4) are shown in Table 1.

Next, the methacrylic resin (B) used in the present invention will be described.
[Methacrylic resin (B-1)]
Parapet GH-1000S (Kuraray Co., Ltd., refractive index: 1.4878)
[Methacrylic resin (B-2)]
Agglomerated powder of copolymer (refractive index 1.4841) obtained by polymerizing a monomer mixture comprising 70% by mass of methyl methacrylate and 30% by mass of methyl acrylate

Examples 1-6 and Comparative Examples 4-8
Powdered multilayer structure polymer particles (A-1) to (A-3) and (4) obtained in Reference Examples 1 to 4, and methacrylic resins (B-1) and (B-2) Dry blending was performed at the ratio shown in Table 2, and the blended product was put into an injection molding machine (SG-150 manufactured by Sumitomo Heavy Industries, Ltd.) and injection molded at a cylinder temperature of 190 ° C and a mold temperature of 50 ° C. A sample for measurement of the optical article for processing was obtained. About this sample, it measured and evaluated about the total light transmittance, the storage elastic modulus, and the secondary workability by said method. The results for each measurement and evaluation are shown in Table 2.

Comparative Example 1
Only the powdered multilayer polymer particles (A-1) obtained in Reference Example 1 were charged into an injection molding machine (SG-150 manufactured by Sumitomo Heavy Industries, Ltd.), and the cylinder temperature was 190 ° C and the mold temperature was 50 ° C. The sample for measurement of the optical article for secondary processing was obtained by injection molding. About this sample, it measured and evaluated about the total light transmittance, the storage elastic modulus, and the secondary workability by said method. The results for each measurement and evaluation are shown in Table 2.

Comparative Example 2
Only the powdered multilayer polymer particles (A-2) obtained in Reference Example 2 were put into an injection molding machine (SG-150 manufactured by Sumitomo Heavy Industries, Ltd.), and the cylinder temperature was 190 ° C and the mold temperature was 50 ° C. The sample for measurement of the optical article for secondary processing was obtained by injection molding. About this sample, it measured and evaluated about the total light transmittance, the storage elastic modulus, and the secondary workability by said method. The results for each measurement and evaluation are shown in Table 2.

Comparative Example 3
Only the methacrylic resin (B-1) is put into an injection molding machine (SG-150 manufactured by Sumitomo Heavy Industries, Ltd.), injection molded at a cylinder temperature of 250 ° C. and a mold temperature of 50 ° C., and an optical article for secondary processing. A sample for measurement was obtained. About this sample, it measured and evaluated about the total light transmittance, the storage elastic modulus, and the secondary workability by said method. The results for each measurement and evaluation are shown in Table 2.

Comparative Example 9
Powdered multilayer structure polymer particles (A-1) obtained in Reference Example 1, pellet-like hard vinyl chloride resin (TH-1000, manufactured by Taiyo PVC Co .; refractive index 1.54; hereinafter referred to as PVC), and dioctyl Tin mercapto-based stabilizer (ONZ-82BF, manufactured by Sansha Kikai Co., Ltd.) was dry blended at the ratio shown in Table 2, and the blended product was injected into an injection molding machine (Sumitomo Heavy Industries, Ltd. SG-150). Then, injection molding was performed at a cylinder temperature of 230 ° C. and a mold temperature of 50 ° C. to obtain a sample for measurement of an optical article for secondary processing. About this sample, it measured and evaluated about the total light transmittance, the storage elastic modulus, and the secondary workability by said method. The results for each measurement and evaluation are shown in Table 2.

  From the results in Table 2, the optical articles for secondary processing of Examples 1 to 6 that satisfy all the constituent requirements of the present invention are in terms of the mass ratio between the multilayer structure polymer particles (A) and the methacrylic resin (B). With respect to the optical articles for secondary processing of Comparative Examples 1 to 3, 5, and 6 that do not satisfy the constituent requirements of the present invention, the storage elastic modulus is in an appropriate range, and the secondary workability is improved.

  From the results in Table 2, the optical article for secondary processing of Example 1 that satisfies all the constituent requirements of the present invention is a rubber component that constitutes the multilayer structured polymer particles instead of the multilayer structured polymer particles (A-1). Optical for secondary processing of Comparative Example 4 using multilayer structure polymer particles (4) that do not satisfy the constituent requirements of the present invention in terms of the difference in refractive index between layer (I) and thermoplastic resin component layer (II) The total light transmittance and secondary processability are improved with respect to the article.

  From the results of Table 2, the optical article for secondary processing of Examples 3 and 4 that satisfies all the constituent requirements of the present invention uses methacrylic resin (B-2) instead of methacrylic resin (B-1). With respect to the optical article for secondary processing of Comparative Examples 7 and 8, which no longer satisfies the requirements for the refractive index difference between the multilayer structure polymer particles (A) and the methacrylic resin (B), total light transmittance and secondary processing Improved.

  Similarly, the optical article for secondary processing of Example 6 that satisfies all the constituent requirements of the present invention is the multilayer structured polymer particles (A-2) or (A−) instead of the multilayer structured polymer particles (A-1). 3), the total light transmission for the secondary processing optical articles of Comparative Examples 7 and 8, which no longer satisfy the requirements of the refractive index difference between the multilayer polymer particles (A) and the methacrylic resin (B). The rate and secondary workability are improved.

  From the results in Table 2, the optical article for secondary processing of Example 3 that satisfies all the constituent requirements of the present invention is compared with Comparative Example 9 in which PVC is used instead of the methacrylic resin (B) defined in the present invention. Total light transmittance and secondary processability are improved.

  According to the present invention, there are provided an optical article for secondary processing having excellent transparency and weather resistance of an acrylic polymer material, and a secondary processed article obtained by subjecting the optical article to heat bending. The secondary processed optical article is suitably used for LED light guides, advertisement display signs, road signs, illuminated game machine housings and covers, decorative key chains, and the like.

A round bar-shaped optical article having a diameter of 2 cm was bent by the composition of Example 2, and a neon sign-shaped display device having a size of about 0.5 m in length and about 2 m in width according to the bending method described in (6) above. It is a figure which shows the usage example of the secondary processing optical article produced by this invention which made the light incident from the light source which was created and located in an end surface.

Claims (6)

An optical article for secondary processing having a minimum length of 5 mm or more of length, width and height obtained by melt-molding a composition comprising a multilayer structure polymer particle (A) and a methacrylic resin (B). The multilayer structure polymer particles (A) are
(1) It comprises two or more layers having at least one of the following rubber component layers (I) inside and at least one of the following thermoplastic resin component layers (II) at least on the outermost portion;
(2) The rubber component layer (I) is composed of 50 to 99.99% by mass of an acrylate ester, 49.99 to 0% by mass of another monofunctional monomer copolymerizable with the acrylate ester, and multifunctional. A polymer layer formed by copolymerization of a monomer mixture (i) comprising 0.01 to 10% by weight of monomers;
(3) The thermoplastic resin component layer (II) is a monomer (ii) comprising 40 to 100% by mass of a methacrylic acid ester and 60 to 0% by mass of another monomer copolymerizable with the methacrylic acid ester. A polymer layer formed by polymerization;
(4) For the polymer constituting the outermost layer of the thermoplastic resin component layer (II), the number average molecular weight measured by the GPC method is 30,000 or less;
(5) The ratio of the total mass of the rubber component layer (I) to the total mass of the thermoplastic resin component layer (II) is in the range of 30/70 to 90/10 in the layer (I) / layer (II). ;
(6) The average particle size is 150 nm or less; and (7) The refractive index n _d (I) of the copolymer constituting any one layer of the rubber component layer (I) and the thermoplastic resin component layer (II ) In any combination with the refractive index n _d (II) of the polymer constituting any one layer;
_{| N d (I) -n d} (II) | <0.005
The composition is characterized by the following requirements (a) and (b):
Requirement (A) The mass ratio of the multilayer polymer particles (A) to the methacrylic resin (B) is 30:70 to 70:30;
In all combinations of the requirement (ii) the rubber component layer refractive index of the polymer constituting any one layer n _{d (I)} and the refractive index n _d of the methacrylic resin (B) of (I) _(B) The following relationship holds:
| N _d (I) −n _d (B) | <0.005
An optical article for secondary processing that satisfies the requirements. An optical article for secondary processing having a minimum length of 5 mm or more of length, width and height obtained by melt-molding a composition comprising a multilayer structure polymer particle (A) and a methacrylic resin (B). The multilayer structure polymer particles (A) are
(1) It has the following rubber component layer (Ia) in the innermost part, and has the following rubber component layer (Ib) in the adjacent part located in a state of covering the outer surface of the innermost part. A three-layer structure having a thermoplastic resin component layer (II);
(2) The rubber component layer (Ia) is composed of 50 to 99.99% by mass of an acrylate ester, 49.99 to 0% by mass of another monofunctional monomer copolymerizable with the acrylate ester, and multifunctional. A polymer layer formed by copolymerization of a monomer mixture (ia) comprising 0.01 to 10% by weight of monomers;
(3) The rubber component layer (Ib) comprises 50 to 99.99% by mass of an acrylate ester, 49.99 to 0% by mass of another monofunctional monomer copolymerizable with the acrylate ester, and polyfunctionality. A polymer layer formed by copolymerization of a monomer mixture (ib) comprising 0.01 to 10% by weight of monomers;
(4) The ratio of the mass of the rubber component layer (Ia) to the mass of the rubber component layer (Ib) is within the range of 5/95 to 95/5 in (Ia) / (Ib);
(5) Difference between acrylic acid ester content (mass%) in monomer mixture (ia) and acrylic acid ester content (mass%) in monomer mixture (ib) [(ia) (unit: % By mass) − (ib) (unit:% by mass)] is 3% by mass or more;
(6) The thermoplastic resin component layer (II) is composed of 40 to 100% by mass of a methacrylic acid ester and 60 to 0% by mass of another monomer copolymerizable with the methacrylic acid ester (ii). A polymer layer formed by polymerization;
(7) For the polymer constituting the thermoplastic resin component layer (II), the number average molecular weight measured by GPC method is 30,000 or less;
(8) The ratio of the total mass of the rubber component layer ((Ia) + (Ib)) to the total mass of the thermoplastic resin component layer (II) is [layer (Ia) + layer (Ib)] / layer (II ) In the range of 30/70 to 90/10;
(9) The average particle diameter is 150 nm or less; and (10) The refractive index n _d (Ia) of the copolymer constituting the rubber component layer (Ia) or the copolymer constituting the rubber component layer (Ib). The following relationship is established between the refractive index n _d (Ib) and the refractive index n _d (II) of the polymer constituting the thermoplastic resin component layer (II);
| N _d (Ia) −n _d (II) | <0.005
| N _d (Ib) −n _d (II) | <0.005
The composition is characterized by the following requirements (a) and (b):
Requirement (A) The mass ratio of the multilayer polymer particles (A) to the methacrylic resin (B) is 30:70 to 70:30;
Requirements (ii) a rubber component layer (Ib) the following relation holds that in the refractive index _n d of constituting the polymer of refractive index _n d (Ib) and methacrylic resin (B) (B);
| N _d (Ib) −n _d (B) | <0.005
The optical article for secondary processing according to claim 1 satisfying The optical article for secondary processing according to claim 1 or 2, wherein a colorant is blended during melt molding. Secondary processing optical article according to any of claims 1 to 3 you blended light stabilizers during melt molding. The storage elastic modulus of dynamic viscoelasticity at 0 ° C. is 6 × 10 ⁸ to 2 × 10 ⁹ Pa, and the storage elastic modulus of dynamic viscoelasticity at 100 ° C. is 5 × 10 ^{7 to} 5 × 10 ⁸ Pa. The optical article for secondary processing according to any one of claims 1 to 4. A secondary processed optical article obtained by heating and bending the optical article according to claim 1.