JP2007177059A - Molding material for lamp housing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a molding material for lamp housings which prevents powdering of a resin, string and blurring around the bonding areas in vibration-welding and drooling between a hot plate and a component material of the lamp housings in hot plate welding, when the lamp housings for vehicles and household electrical appliances and other members (plastic lenses and the like) are bonded. <P>SOLUTION: The molding material contains a rubber-reinforced resin obtained by polymerizing a vinyl monomer containing an aromatic vinyl compound and a cyanide vinyl compound in the presence of an acrylic rubbery polymer with a gel content of less than 70% or a mixture of the rubber-reinforced resin and a (co)polymer of a vinyl monomer(s). The content of the acrylic rubbery polymer is 5-40 mass% of the total weight of the molding materials. The number of drooled strings observed when a test piece of the molding materials is brought in contact with a heated hot plate under specified conditions and then separated from the hot plate is not more than 3. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a molding material for a lamp housing. More specifically, the present invention relates to a lamp housing suitable for joining a lamp housing made of the molding material for vehicles, home appliances, etc., and other members (resin lens, etc.). It relates to molding materials.

Lamp housings for two-wheeled vehicles, four-wheeled vehicles, and home appliances are manufactured using, for example, a thermoplastic resin composition disclosed in Patent Literature 1, Patent Literature 2, and the like. For example, in order to use a lamp housing as a vehicle lamp, the peripheral part of the lamp housing and the peripheral part of the resin lens are joined by a method such as a vibration welding method, a hot plate welding method, or a laser welding method. .
According to the vibration welding method, resin powder, (yarn) burrs, collapsed burrs, etc. may occur around the joint. Also, according to the hot plate welding method, the components of the lamp housing are changed from the thermal type. When the planned joining portion where the (resin component) is melted leaves, stringing or the like may occur. These defective phenomena reduce the appearance of the lamp.
In order to further increase the luminance of the emitted lamp, a light reflecting surface is usually formed by a surface treatment such as providing a metal layer on the inner surface of the lamp housing. As the surface treatment, reflective coating treatment, vapor deposition treatment or the like is performed. Under recent environmental problems, undercoatless metallization capable of reducing VOC is becoming the mainstream of surface treatment. However, when the undercoat is not performed, there is a problem that the brightness is lowered due to the fine unevenness present on the surface of the molded product, and the present situation is that a good brightness cannot be obtained unless the undercoat is performed.
Since the above-mentioned defect phenomenon is considered to depend largely on the resin component, attempts have been made to devise molecular design of resin components, production methods, and the like. For example, Patent Document 2 discloses a thermoplastic resin composition containing a rubber-reinforced resin using a rubbery polymer having a gel content of 70% or more, a maleimide copolymer, and the like.

JP 11-199727 A JP 2004-182835 A

  The present invention has been made based on the above-described technical background, and uses a vibration welding method when joining a lamp housing for a vehicle, a household appliance, or the like and another member (resin lens, etc.). In this case, it is possible to suppress the occurrence of resin powder, (thread) burrs, etc. in the vicinity of the joint, and in the case of the hot plate welding method, stringing is performed between the heat type such as the hot plate and the constituent material of the housing. An object of the present invention is to provide a lamp housing molding material that can suppress the occurrence of the above and the like and is excellent in luminance.

The present invention is as follows.
1. An acrylic polymer obtained by polymerizing a vinyl monomer [b1] containing an aromatic vinyl compound and a vinyl cyanide compound in the presence of an acrylic rubbery polymer [a1] having a toluene gel content of less than 70%. For a lamp housing containing a rubber-reinforced vinyl resin [A1] or a mixture of the acrylic rubber-reinforced vinyl resin [A1] and a (co) polymer [A2] of a vinyl monomer [b2] It is a molding material, and the content of the acrylic rubbery polymer [a1] is 5 to 40% by mass with respect to the total amount of the molding material for the lamp housing, and is made of the molding material for the lamp housing. A specimen having a length of 100 mm, a width of 30 mm and a thickness of 3 mm was conditioned for 3 hours at a temperature of 23 ° C. and a relative humidity of 50%, and then brought into contact with a heated hot plate under the following test conditions. Molding material for lamp housing, wherein the number of stringing observed when released al is equal to or less than three.
〔Test conditions〕
Hot plate temperature: 280 ° C
Movement speed: 200 mm / second contact time of test piece and hot plate; 15 second melting amount of test piece; 0.5 mm
2. The acrylic rubbery polymer [a1] is an acrylic acid alkyl ester (m1) having an alkyl group having 1 to 12 carbon atoms, a compound (m2) copolymerizable with the acrylic acid alkyl ester (m1), A copolymer having a volume average particle diameter of 40 to 190 nm and a toluene swelling degree of 6 to 20 obtained by copolymerizing with a polyfunctional vinyl compound (m3), and the acrylic acid alkyl ester (m1) ) And the compound (m2) are used in a proportion of 60 to 100% by mass and 0 to 40% by mass, respectively, and the polyfunctional vinyl compound (m3) 2. The lamp housing according to 1 above, wherein the amount used is 0.1 to 10 parts by mass with respect to 100 parts by mass of the total amount of the alkyl acrylate ester (m1) and the compound (m2). Ring for the molding material.
3. The acrylic rubbery polymer [a1] is an alkyl acrylate ester (m11) having an alkyl group having 1 to 12 carbon atoms, a compound (m21) copolymerizable with the alkyl acrylate ester (m11), and The first step of copolymerizing the polyfunctional vinyl compound (m31) at a polymerization conversion rate of 85% or more, and having an alkyl group having 1 to 12 carbon atoms in the presence of the copolymer obtained in the first step A second copolymerization of an acrylic acid alkyl ester (m12), a compound (m22) copolymerizable with the acrylic acid alkyl ester (m12), and a polyfunctional vinyl compound (m32) at a polymerization conversion rate of 85% or more. A total amount of the acrylic acid alkyl ester (m11) and the compound (m21) used in the first step is a polymer obtained from the method comprising: When the total amount of the acrylic acid alkyl esters (m11) and (m12) and the compounds (m21) and (m22) is 100% by mass, the polyfunctional vinyl compound (m31) is 50 to 90% by mass. Is used in an amount of 0.01 to 0.3 parts by mass when the total amount of the alkyl acrylate ester (m11) and the compound (m21) is 100 parts by mass, and the second step is the above. The total amount of the alkyl acrylate (m12) and the compound (m22) used is 100% by mass of the total amount of the alkyl acrylates (m11) and (m12) and the compounds (m21) and (m22). The amount of the polyfunctional vinyl compound (m32) used is 10% by mass to 50% by mass. 12) and when the compound the total amount of (m22) is 100 parts by mass, the molding material for lamp housing according to claim 1 or 2 is 0.5 to 10 parts by weight.
4). 4. The molding material for a lamp housing according to any one of 1 to 3 above, wherein a deflection temperature under load (Under Load) according to ISO75 is 80 ° C. or higher.
In the present invention, the compound (m2), the compound (m21) and the compound (m22) are all compounds that can be copolymerized with an alkyl acrylate and do not contain a polyfunctional vinyl compound. .

  The molding material for lamp housing of the present invention comprises a vinyl monomer [b1] containing an aromatic vinyl compound and a vinyl cyanide compound in the presence of an acrylic rubber polymer [a1] having a toluene gel content of less than 70%. ], Or a (co) polymer [A2] of the acrylic rubber-reinforced vinyl resin [A1] and the vinyl monomer [b2]. In the case of using a vibration welding method when joining a lamp housing for vehicles, home appliances, etc., and other members (resin lenses, etc.), the resin powder around the joint is used. Body, (thread) burrs, etc. can be suppressed, and in the case of the hot plate welding method, the occurrence of stringing, etc. can be suppressed between the thermal type such as the hot plate and the constituent material of the housing. . In addition, an excellent lamp brightness can be obtained when a metal layer such as chromium or aluminum is directly formed by sputtering or vacuum deposition without subjecting the surface of the molded product to undercoating.

  The molding material for the lamp housing of the present invention is useful as a molding material that provides a lamp housing suitable for any of the vibration welding method, the hot plate welding method, and the laser welding method, and an apparatus used for the molding process of the lamp housing, It is possible to simplify the switching of materials and the like, which is extremely industrial value.

Hereinafter, the present invention will be described in detail.
The molding material for lamp housing of the present invention comprises an aromatic vinyl compound and cyanide in the presence of an acrylic rubbery polymer [a1] having a toluene gel content (hereinafter simply referred to as “gel content”) of less than 70%. An acrylic rubber-reinforced vinyl resin [A1] obtained by polymerizing a vinyl monomer [b1] containing a vinyl compound, or the acrylic rubber-reinforced vinyl resin [A1] and a vinyl monomer [A1]. b2] (co) polymer [A2] and a mixture for the lamp housing, wherein the content of the acrylic rubbery polymer [a1] is the total amount of the lamp housing molding material. The test piece made of the molding material for the lamp housing is in contact with a heated hot plate under specific conditions, and then observed when separated from the hot plate. Is Wherein the number of stringing is less than three. In the present specification, “(co) polymerization” means homopolymerization and copolymerization, and “(meth) acryl” means acryl and methacryl.

1. Acrylic rubber reinforced vinyl resin [A1]
The acrylic rubbery polymer [a1] used for the formation of the acrylic rubber-reinforced vinyl resin [A1] is a (co) polymer made of a monomer containing a (meth) acrylic acid alkyl ester. There is no particular limitation.

The monomer preferably includes an alkyl acrylate ester having an alkyl group having 1 to 12 carbon atoms (hereinafter referred to as “alkyl acrylate ester (m1)”).
As the alkyl acrylate ester (m1), methyl acrylate, ethyl acrylate, n-propyl acrylate, i-propyl acrylate, n-butyl acrylate, i-butyl acrylate, tert-butyl acrylate, acrylic acid Examples include amyl, n-hexyl acrylate, n-octyl acrylate, 2-ethylhexyl acrylate, dodecyl acrylate, cyclohexyl acrylate, phenyl acrylate, and benzyl acrylate. Of these compounds, n-butyl acrylate and 2-ethylhexyl acrylate are preferred. These alkyl acrylate esters (m1) can be used alone or in combination of two or more.

  The acrylic rubbery polymer [a1] may be a homopolymer using one of the alkyl acrylate esters (m1) or a copolymer using two or more. Good. Further, it may be a copolymer using one or more kinds of acrylic acid alkyl ester (m1) and one or more kinds of compound (m2) copolymerizable with this acrylic acid alkyl ester (m1), Furthermore, even if it is a copolymer using 1 or more types of alkyl acrylate ester (m1), 1 or more types of a compound (m2), and 1 or more types of a polyfunctional vinyl compound (m3), Good.

  The compound (m2) is not particularly limited as long as it is a compound that can be copolymerized with the alkyl acrylate ester (m1) and does not contain the polyfunctional vinyl compound (m3). Group vinyl compounds, monofunctional vinyl cyanide compounds, diene compounds and the like. These may be used alone or in combination.

  Monofunctional aromatic vinyl compounds include styrene, α-methyl styrene, o-methyl styrene, p-methyl styrene, vinyl toluene, β-methyl styrene, ethyl styrene, p-tert-butyl styrene, vinyl xylene, vinyl naphthalene. Etc. Of these, styrene is preferred. Moreover, these compounds can be used individually by 1 type or in combination of 2 or more types.

Examples of the vinyl cyanide compound include acrylonitrile, methacrylonitrile, ethacrylonitrile and the like. Of these, acrylonitrile is preferred. Moreover, these compounds can be used individually by 1 type or in combination of 2 or more types.
Examples of the diene compound include butadiene and isoprene. These compounds can be used alone or in combination of two or more.

  The polyfunctional vinyl compound (m3) is not particularly limited as long as it is a compound having two or more vinyl groups in one molecule. For example, bifunctional aromatic vinyl such as divinylbenzene and divinyltoluene. Compound: Allyl (meth) acrylate, 1,6-hexanediol di (meth) acrylate, ethylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, 3-methyl Bifunctional (meth) acrylic acid esters such as pentanediol di (meth) acrylate; trifunctionality such as trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, trimethylolpropane tri (meth) acrylate ( (Meth) acrylic acid ester; (Meth) acrylic acid esters of polyhydric alcohols such as taerythritol tetra (meth) acrylate, pentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, (poly) ethylene glycol di (meth) acrylate; Examples thereof include rate, diallyl fumarate, triallyl cyanurate, triallyl isocyanurate, diallyl phthalate, and bis (acryloyloxyethyl) ether of bisphenol A. Of these compounds, allyl methacrylate and triallyl cyanurate are preferred. Moreover, these polyfunctional vinyl compounds (m3) can be used individually by 1 type or in combination of 2 or more types.

The acrylic rubbery polymer [a1] is preferably a copolymer obtained by using the above compounds (m1), (m2) and (m3) in the following amounts.
The amount of the acrylic acid alkyl ester (m1) and the compound (m2) used is preferably 60 to 100% by mass and 0 to 40% by mass, more preferably 70 to 100%, when the total amount is 100% by mass. The mass% and 0 to 30 mass%, more preferably 80 to 100 mass% and 0 to 20 mass%.
The amount of the polyfunctional vinyl compound (m3) used is preferably 0.1 to 10 parts by mass, more preferably 100 parts by mass when the total of the acrylic acid alkyl ester (m1) and the compound (m2) is 100 parts by mass. It is 0.1-8 mass parts, More preferably, it is 0.15-7 mass parts. By setting the amount of each compound used within the above range, an acrylic rubber-reinforced vinyl resin [A1] suitable for a molding material for a lamp housing suitable for any of the vibration welding method, hot plate welding method and laser welding method. It can be a forming polymer component.

  The acrylic rubbery polymer [a1] may be polymerized in the presence of the total amount of the compounds (m1), (m2) and (m3), and the preferred amount used. It is also possible to divide and use within the range and to perform multistage polymerization. In the latter case, for example, an acrylic rubber polymer can be obtained by two-stage polymerization, which will be described below.

As the acrylic rubbery polymer by two-stage polymerization, an alkyl acrylate ester (m11) having an alkyl group having 1 to 12 carbon atoms, a compound (m21) copolymerizable with the acrylate alkyl ester (m11), and , A first step of copolymerizing the polyfunctional vinyl compound (m31) at a polymerization conversion rate of 85% or more, and an alkyl group having 1 to 12 carbon atoms in the presence of the copolymer obtained in the first step. The acrylic acid alkyl ester (m12), the compound (m22) copolymerizable with the alkyl alkyl ester (m12), and the polyfunctional vinyl compound (m32) are copolymerized at a polymerization conversion rate of 85% or more. It can be obtained by a method comprising two steps. The compounds (m21) and (m22) can be copolymerized with the acrylic acid alkyl ester (m11) or (m12), respectively, and do not contain the polyfunctional vinyl compound (m31) or (m32). It is.
In addition, said acrylic acid alkyl ester (m11) and (m12), compound (m21) and (m22), and polyfunctional vinyl compound (m31) and (m32) are respectively said acrylic acid alkyl ester ( The compounds exemplified as m1), the compound (m2), and the polyfunctional vinyl compound (m3) can be used. Moreover, about each of these raw materials, the use compound in a 1st process and the use compound in a 2nd process may be the same, and may differ.

Acrylic acid alkyl ester (m11), compound (m21) and multifunctional vinyl compound (m31) in the first step, and Acrylic acid alkyl ester (m12), compound (m22) and multifunctional vinyl compound in the second step Each usage amount of (m32) is as follows.
The total amount of the acrylic acid alkyl ester (m11) and the compound (m21) used in the first step is the total amount of the acrylic acid alkyl esters (m11) and (m12) and the compounds (m21) and (m22). Is preferably 50 to 90% by mass, more preferably 60 to 90% by mass, still more preferably 65 to 85% by mass, and the amount of the polyfunctional vinyl compound (m31) used is as follows: When the total amount of the alkyl acrylate ester (m11) and the compound (m21) is 100 parts by mass, preferably 0.01 to 0.3 parts by mass, more preferably 0.05 to 0.25 parts by mass, More preferably 0.08 to 0.20 parts by mass, and the alkyl acrylate (m12) and the compound in the second step The total amount of (m22) used is preferably 10 to 50% by mass when the total amount of the alkyl alkyl esters (m11) and (m12) and the compounds (m21) and (m22) is 100% by mass. More preferably, it is 10-40 mass%, More preferably, it is 15-35 mass%, and the usage-amount of the said polyfunctional vinyl compound (m32) is the acrylic acid alkyl ester (m12) and the said compound (m22). When the total amount is 100 parts by mass, it is preferably 0.5 to 10 parts by mass, more preferably 1 to 8 parts by mass, and still more preferably 2 to 7 parts by mass.
Thus, the polymer obtained by the method including the first and second steps is considered to have a multilayer structure such as a so-called core-shell structure. That is, the core portion is formed by the first step, and then the shell portion is formed by the second step. When the usage amount of each polyfunctional vinyl compound used in the first and second steps is compared, since the usage ratio used in the second step is high, the shell portion formed in the second step is formed in the first step. It is considered that an acrylic rubbery polymer having a structure harder than the core portion thus formed is formed.

The acrylic rubbery polymer [a1] is preferably applied by emulsion polymerization in both cases of batch polymerization and production by multistage polymerization.
Emulsion polymerization is usually performed while stirring and heating a mixture containing a monomer, an emulsifier, a polymerization initiator, and water. In addition, you may add a molecular weight modifier, a chain transfer agent, an electrolyte, etc. to a reaction system.

Examples of the emulsifier include alkyl sulfonates such as alkane sulfonate, alkyl benzene sulfonate, and alkyl naphthalene sulfonate; alkyl sulfate ester salt; polyoxyethylene alkyl ether sulfate ester salt; polyoxyethylene alkyl ether ether; alkyl sulfosuccinate salt Polyoxyethylene fatty acid ester; sorbitan fatty acid ester; glycerin fatty acid ester; alkyl phosphate ester salt; rosin acid salt and the like. These can be used alone or in combination of two or more.
The rosinate is an alkali of rosin acid (usually mainly composed of abietic acid) such as gum rosin, wood rosin, tall oil rosin, disproportionated rosin obtained by disproportionating these, and purified rosin. Metal salt, usually sodium salt or potassium salt.
The amount of the emulsifier used is usually 0.1 to 20 parts by mass, preferably 0.5 to 5 parts by mass, when the total amount of monomers used is 100 parts by mass.

  Examples of the polymerization initiator include organic peroxides such as cumene hydroperoxide, diisopropylbenzene hydroperoxide, paramentane hydroperoxide, benzoyl peroxide, lauroyl peroxide, tert-butyl peroxylaurate, and tert-butyl peroxymonocarbonate. Oxides; azo compounds such as azobisisobutyronitrile; persulfates such as potassium persulfate; These can be used alone or in combination of two or more. The polymerization initiator can be added to the reaction system all at once, continuously or divided. Moreover, the usage-amount of the said polymerization initiator is 0.001-5 mass parts normally, when the whole quantity of the monomer to be used is 100 mass parts, Preferably it is 0.01-3 mass parts.

Examples of molecular weight regulators include mercaptans such as n-hexyl mercaptan, n-octyl mercaptan, n-dodecyl mercaptan, tert-dodecyl mercaptan, 2-mercaptoethanol, pentaerythritol tetrakis (β-mercaptopropionate), and limonene dimercaptan. And n-dodecylthiol acetate, 2-ethylhexyl thioglycolate and the like. These can be used alone or in combination of two or more.
The amount of the molecular weight regulator used is usually 0 to 5 parts by mass, preferably 0 to 2 parts by mass, when the total amount of monomers used is 100 parts by mass.
Of the above molecular weight regulators, mercaptans can also be used as chain transfer agents.

Examples of the chain transfer agent include the above-mentioned mercaptans, tetraethylthiuram sulfide, acrolein, methacrolein, allyl alcohol, 2-ethylhexylthioglycol and the like. These can be used alone or in combination of two or more.
The amount of the chain transfer agent used is usually 0 to 5 parts by mass, preferably 0 to 3 parts by mass, when the total amount of monomers used is 100 parts by mass.

  The polymerization temperature in the emulsion polymerization is usually 10 to 95 ° C, preferably 30 to 90 ° C, more preferably 35 to 85 ° C.

The gel content of the acrylic rubbery polymer [a1] is less than 70%, preferably 30 to 69.5%, more preferably 45 to 69%. Within this range, an acrylic rubber-reinforced vinyl resin [A1] forming polymer component suitable for a lamp housing molding material suitable for any of the vibration welding method, hot plate welding method and laser welding method; can do. This gel content, when producing the acrylic rubber polymer [a1], the type and amount of the polyfunctional vinyl compound used, the type and amount of the molecular weight regulator, polymerization time, polymerization temperature, polymerization conversion rate, etc. It adjusts by selecting suitably.
In addition, the measuring method of the said gel content is as follows.
First, 1 gram of the acrylic rubbery polymer [a1] is put into 20 ml of toluene, and stirred at 1,000 rpm for 2 hours using a stirrer. Thereafter, the mixture is centrifuged for 1 hour with a centrifuge (rotation speed: 22,000 rpm), the insoluble matter obtained by separating the insoluble matter and the soluble matter is weighed (the mass is W1 gram), and further insoluble. After the minutes are dried, they are weighed (mass is W2 grams) and calculated by the following formula.
Gel content (%) = [W2 (g) / 1 (g)] × 100

The volume average particle diameter of the acrylic rubbery polymer [a1] is preferably 40 to 190 nm, more preferably 50 to 170 nm, and still more preferably 60 to 150 nm. When the volume average particle diameter is in the above range, when a molded product is obtained, the smoothness of the surface is good and the luminance is also excellent.
Moreover, the toluene swelling degree of acrylic rubber-like polymer [a1] becomes like this. Preferably it is 6-20, More preferably, it is 7-20, More preferably, it is 9-18. When this degree of toluene swelling is in the above range, an acrylic rubber-reinforced vinyl resin [A1] suitable for a lamp housing molding material suitable for any of the vibration welding method, hot plate welding method and laser welding method is formed. The polymer component can be used. In addition, this toluene swelling degree can be calculated by the following formula using the mass before drying (W1 gram) and the mass after drying (W2 gram) obtained when calculating the gel content. .
Toluene swelling = [W1 (g) / W2 (g)]
The acrylic rubbery polymer [a1] can be used alone or in combination of two or more.

  The acrylic rubber-reinforced vinyl resin [A1] of the present invention comprises a vinyl monomer [b1] containing an aromatic vinyl compound and a vinyl cyanide compound in the presence of the acrylic rubbery polymer [a1]. It was obtained by polymerization.

  Examples of the aromatic vinyl compound include styrene, α-methylstyrene, o-methylstyrene, p-methylstyrene, vinyltoluene, vinylxylene, ethylstyrene, dimethylstyrene, methyl-α-methylstyrene, p-tert-butylstyrene, Examples thereof include vinyl naphthalene, monobromostyrene, dibromostyrene, tribromostyrene, and fluorostyrene. Of these, styrene and α-methylstyrene are preferred. Moreover, these compounds can be used individually by 1 type or in combination of 2 or more types.

  Examples of the vinyl cyanide compound include acrylonitrile, methacrylonitrile, ethacrylonitrile, fumaronitrile and the like. Of these, acrylonitrile is preferred. Moreover, these compounds can be used individually by 1 type or in combination of 2 or more types.

  In addition to the above aromatic vinyl compound and vinyl cyanide compound, the vinyl monomer [b1] may be other compounds copolymerizable with these. Other compounds include (meth) acrylic acid alkyl esters, maleimide compounds, functional group-containing unsaturated compounds (eg, unsaturated acids, epoxy group-containing unsaturated compounds, hydroxyl group-containing unsaturated compounds, oxazoline group-containing unsaturated compounds) , Acid anhydride group-containing unsaturated compounds, etc.). These can be used alone or in combination of two or more.

Examples of (meth) acrylic acid alkyl esters include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, amyl (meth) acrylate, and (meth) acrylic acid. Examples include hexyl, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, phenyl (meth) acrylate, and benzyl (meth) acrylate. These compounds can be used alone or in combination of two or more.
Examples of the unsaturated acid include (meth) acrylic acid, itaconic acid, maleic acid and the like. These compounds can be used alone or in combination of two or more.

  Examples of the maleimide compound include maleimide, N-methylmaleimide, N-butylmaleimide, N-phenylmaleimide, N-cyclohexylmaleimide and the like. These compounds can be used alone or in combination of two or more. In order to introduce a maleimide monomer unit into the polymer, maleic anhydride may be (co) polymerized and then imidized.

  Examples of the epoxy group-containing unsaturated compound include glycidyl (meth) acrylate, β-methylglycidyl (meth) acrylate, β-ethylglycidyl (meth) acrylate, and 3-methyl-3,4-epoxy (meth) acrylate. Butyl, 3-ethyl-3,4-epoxybutyl (meth) acrylate, 4-methyl-4,5-epoxypentyl (meth) acrylate, 2,3-epoxycyclohexylmethyl (meth) acrylate, (meth) 3,4-epoxycyclohexylmethyl acrylate, o-vinylbenzylglycidyl ether, m-vinylbenzylglycidyl ether, p-vinylbenzylglycidyl ether, 2-vinylcyclohexene oxide, 3-vinylcyclohexene oxide, 4-vinylcyclohexene oxide, allyl Glycidyl ether Etc. These compounds can be used alone or in combination of two or more.

  Examples of the hydroxyl group-containing unsaturated compound include 3-hydroxy-1-propene, 4-hydroxy-1-butene, cis-4-hydroxy-2-butene, trans-4-hydroxy-2-butene, and 3-hydroxy-2. -Methyl-1-propene, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 1-hydroxypropyl (meth) acrylate, hydroxycyclohexyl (meth) acrylate, N- ( 4-hydroxyphenyl) maleimide and the like. These compounds can be used alone or in combination of two or more.

Examples of the oxazoline group-containing unsaturated compound include vinyl oxazoline. These compounds can be used alone or in combination of two or more.
Examples of the acid anhydride group-containing unsaturated compound include maleic anhydride, itaconic anhydride, citraconic anhydride, and the like. These compounds can be used alone or in combination of two or more.

  As the vinyl monomer [b1], it is preferable to mainly use an aromatic vinyl compound and a vinyl cyanide compound, and the total amount of these compounds is preferably relative to the total amount of the vinyl monomer [b1]. Is 75% by mass or more, more preferably 80% by mass or more, and further preferably 90% by mass or more. Moreover, each usage-amount of an aromatic vinyl compound and a vinyl cyanide compound becomes like this. When these sum total is 100 mass%, Preferably it is 5-95 mass% and 5-95 mass%, respectively, More preferably, it is 50-90, respectively. It is 10 mass% and 10-50 mass%.

  The production method of the acrylic rubber-reinforced vinyl resin [A1] is not particularly limited, and can be obtained by a known method such as emulsion polymerization, bulk polymerization, solution polymerization, suspension polymerization. Of these, emulsion polymerization is preferred. In addition, each usage-amount of acrylic-type rubber-like polymer [a1] and vinyl-type monomer [b1], When these sum total is 100 mass%, Preferably it is 5-95 mass% and 5-95, respectively. It is mass%, More preferably, they are 30-80 mass% and 20-70 mass%.

When the acrylic rubber-reinforced vinyl resin [A1] is produced by emulsion polymerization, as in the case of producing the acrylic rubbery polymer [a1] by emulsion polymerization, an emulsifier, a polymerization initiator, a molecular weight regulator, a chain A transfer agent, electrolyte, water, or the like can be used, and the above examples can be applied to these types.
As the polymerization initiator, in addition to the above, a redox initiator based on a combination of the organic peroxide and a reducing agent such as a sugar-containing pyrophosphate formulation or a sulfoxylate formulation can also be used.

The amount of the emulsifier is preferably 0.1 to 5 parts by mass, more preferably 0.5 to 3 parts by mass, when the total amount of the vinyl monomer [b1] is 100 parts by mass.
The amount of the polymerization initiator used is preferably 0.01 to 5 parts by mass, more preferably 0.1 to 3 parts by mass when the total amount of the vinyl monomer [b1] is 100 parts by mass. This polymerization initiator can be added to the reaction system all at once or continuously.
The amount of the molecular weight regulator used is preferably 0 to 3 parts by mass, more preferably 0 to 1 part by mass, when the total amount of the vinyl monomer [b1] is 100 parts by mass.
The amount of the chain transfer agent used is preferably 0 to 5 parts by mass, more preferably 0.01 to 2 parts by mass when the total amount of the vinyl monomer [b1] is 100 parts by mass.

When the acrylic rubber-reinforced vinyl resin [A1] is produced by emulsion polymerization, the acrylic rubbery polymer [a1] and the vinyl monomer [b1] are used in accordance with the acrylic rubbery polymer [A1]. a1] In the presence of the total amount, the vinyl monomer [b1] may be added all at once and polymerized, or divided or continuously added. Further, in the presence of a part of the acrylic rubber polymer [a1], the vinyl monomer [b1] is added all at once, and the remainder of the acrylic rubber polymer [a1] is added during the polymerization. Alternatively, the vinyl monomer [b1] may be divided or continuously added, and the remainder of the acrylic rubber polymer [a1] may be added during the polymerization.
The polymerization temperature in the emulsion polymerization is usually 10 to 95 ° C, preferably 30 to 90 ° C, more preferably 35 to 85 ° C.

  In order to take out the acrylic rubber-reinforced vinyl resin [A1] from the latex obtained by emulsion polymerization of the vinyl monomer [b1] in the presence of the acrylic rubbery polymer [a1] , A coagulant is added. Thereafter, the solidified acrylic rubber-reinforced vinyl resin [A1] is obtained as a uniform powder by filtration, washing with water, and drying as appropriate. Examples of the coagulant include inorganic salts such as calcium chloride, magnesium sulfate and magnesium chloride, and acids such as sulfuric acid, hydrochloric acid and acetic acid.

When the acrylic rubber-reinforced vinyl resin [A1] is produced by solution polymerization, a solvent, a polymerization initiator, a chain transfer agent, or the like is usually used. It can also be produced without using a polymerization initiator.
Examples of the solvent include inert polymerization solvents used in known radical polymerization, for example, aromatic hydrocarbons such as ethylbenzene and toluene; ketones such as methyl ethyl ketone and acetone; halogenated hydrocarbons such as dichloromethylene and carbon tetrachloride. Acetonitrile, dimethylformamide, N-methylpyrrolidone and the like can be used.

Examples of the polymerization initiator include organic peroxides such as ketone peroxide, dialkyl peroxide, diacyl peroxide, peroxy ester, and hydroperoxide.
Examples of the chain transfer agent include mercaptans, α-methylstyrene dimer, terpinolene and the like.

When the acrylic rubber-reinforced vinyl resin [A1] is produced by solution polymerization, the production conditions are appropriately selected according to the types of the vinyl monomer [b1] and the polymerization initiator used. The acrylic rubbery polymer [a1] and the vinyl monomer [b1] are used by adding the vinyl monomer [b1] at once in the presence of the entire amount of the acrylic rubbery polymer [a1]. May be polymerized, or may be divided or continuously added. Further, in the presence of a part of the acrylic rubber polymer [a1], the vinyl monomer [b1] is added all at once, and the remainder of the acrylic rubber polymer [a1] is added during the polymerization. Alternatively, the vinyl monomer [b1] may be divided or continuously added, and the remainder of the acrylic rubber polymer [a1] may be added during the polymerization.
The polymerization temperature during solution polymerization is preferably in the range of 0 to 150 ° C.

  Also in the case of bulk polymerization and suspension polymerization, known methods can be applied. As the polymerization initiator, chain transfer agent and the like used in these methods, the compounds exemplified in the explanation of the solution polymerization can be used.

  In the acrylic rubber-reinforced vinyl resin [A1] produced by a method such as emulsion polymerization or solution polymerization, a (co) polymer of the vinyl monomer [b1] is usually an acrylic rubbery polymer [a1]. And a copolymer of the vinyl monomer [b1] and an ungrafted component (a copolymer of the vinyl monomer [b1] (copolymer) which is not grafted to the acrylic rubber polymer [a1]. ) Polymer).

The graft ratio of the acrylic rubber-reinforced vinyl resin [A1] is preferably 30 to 200%, more preferably 40 to 150%, and still more preferably 50 to 110%. If this graft ratio is in the above range, an acrylic rubber-reinforced vinyl resin suitable for a lamp housing molding material suitable for any of the vibration welding method, hot plate welding method and laser welding method can be obtained. it can. The graft ratio (%) is obtained by the following formula.
Graft rate (%) = {(S−T) / T} × 100
In the above formula, S is a mixture of 1 g of acrylic rubber-reinforced vinyl resin [A1] into 20 ml of acetonitrile, shaken with a shaker for 2 hours, and then centrifuged with a centrifuge (rotation speed: 23,000 rpm). This is the mass (g) of the insoluble matter obtained by centrifugal separation and separating the insoluble matter and the soluble matter, and T is the acrylic rubbery material contained in 1 gram of the acrylic rubber-reinforced vinyl resin [A1]. It is the mass (g) of the polymer [a1].

  Moreover, the intrinsic viscosity [η] of acetonitrile-soluble component of the acrylic rubber-reinforced vinyl resin [A1] (measured at 25 ° C. using methyl ethyl ketone as a solvent) is preferably 0.1 to 1.0 dl / g, More preferably, it is 0.1-0.8 dl / g, More preferably, it is 0.15-0.70 dl / g.

2. (Co) polymer [A2]
The vinyl monomer [b2] used for forming the (co) polymer [A2] is preferably an aromatic vinyl compound, a vinyl cyanide compound, a (meth) acrylic acid alkyl ester, a maleimide compound, and a functional group. It is 1 or more types of a contained unsaturated compound (For example, an unsaturated acid, an epoxy group containing unsaturated compound, a hydroxyl group containing unsaturated compound, an oxazoline group containing unsaturated compound, an acid anhydride group containing unsaturated compound, etc.). Particularly preferred are at least one of an aromatic vinyl compound, a vinyl cyanide compound, a (meth) acrylic acid ester and a maleimide compound. In addition, what was illustrated in the said vinyl-type monomer [b1] used for manufacture of said acrylic rubber-reinforced vinyl-type resin [A1] can be used for said each compound.

Examples of the (co) polymer [A2] include the following. These can be used alone or in combination of two or more.
(1) Styrene / acrylonitrile copolymer (2) Styrene / acrylonitrile / methyl methacrylate copolymer (3) α-methylstyrene / acrylonitrile copolymer (4) α-methylstyrene / acrylonitrile / methyl methacrylate copolymer (5) Styrene / α-methylstyrene / acrylonitrile copolymer (6) Styrene / N-phenylmaleimide copolymer (7) Styrene / acrylonitrile / N-phenylmaleimide copolymer (8) Methyl methacrylate / styrene copolymer Copolymer (9) Methyl methacrylate / α-methylstyrene copolymer (10) Polystyrene (11) Poly α-methylstyrene (12) Polymethyl methacrylate

3. Molding Material for Lamp Housing The molding material for lamp housing of the present invention (hereinafter also referred to as “the molding material of the present invention”) is an acrylic rubber-reinforced vinyl resin [A1] or the acrylic rubber-reinforced vinyl resin. It contains a mixture consisting of [A1] and (co) polymer [A2].
Therefore, the molding material of the present invention may be only the above-mentioned acrylic rubber-reinforced vinyl resin [A1] or only the above mixture, and these and other components (polymer, additive, etc.) And a mixture thereof.
In any of the above cases, the content of the acrylic rubber polymer [a1] in the molding material of the present invention is 5 to 40% by mass, preferably 5 to 35% by mass, more preferably 10 to 30%. % By mass. If it is this range, it can be set as the molding material for lamp housings suitable for any method of a vibration welding method, a hot plate welding method, and a laser welding method.

In the molding material of the present invention, a polymer (resin), an additive and the like can be further blended in order to improve the target performance of the present invention.
Examples of the polymer (resin) include ABS resin, HIPS resin, AES resin, silicone rubber reinforced resin, hydrogenated rubber reinforced resin, ASA resin (excluding acrylic rubber reinforced vinyl resin [A1] according to the present invention), and the like. Rubber reinforced resin, polyethylene, polypropylene, ionomer, ethylene / vinyl acetate copolymer, ethylene / vinyl alcohol copolymer, cyclic olefin copolymer, olefinic resin such as chlorinated polyethylene; polyamide 6, polyamide 6,6, Polyamide resins such as polyamide 6,12; polyester resins such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene naphthalate; polycarbonate resins; polyacetal resins; liquid crystal polymers. These can be used alone or in combination of two or more. Of these, rubber reinforced resins are preferred.
The blending amount of the polymer (resin) is preferably when the total amount of polymer components including the acrylic rubber-reinforced vinyl resin [A1] and (co) polymer [A2] is 100 parts by mass. 1 to 30 parts by mass.

  Examples of additives include fillers, ultraviolet absorbers, antioxidants, flame retardants, compatibilizers, heat stabilizers, light stabilizers, antistatic agents, lubricants, mold release agents, antibacterial agents, and coloring agents. It is done.

As a filler, what consists of a metal (an alloy is included), an inorganic compound, a high molecular compound, etc. can be used. Moreover, what consists of a composite material containing these 2 or more types can also be used.
Examples of the metal include stainless steel, aluminum, titanium, copper, and brass. Inorganic compounds include oxides (alumina, zirconia, etc.), nitrides (silicon nitride, boron nitride, etc.), carbides (silicon carbide, etc.), carbonates (calcium carbonate, magnesium carbonate, etc.), sulfates (calcium sulfate, etc.) Silicates (silica, quartz, glass, calcium oxalate, aluminum oxalate, kaolin, clay, diatomaceous earth, etc.), nitrates, phosphates and the like.
The shape of the filler is not particularly limited, and examples thereof include particles, fibers, plates, and lumps. Examples of the fibrous filler include glass fiber, carbon fiber, silica fiber, silica / alumina fiber, zirconia fiber, boron nitride fiber, silicon nitride fiber, boron fiber, and potassium titanate whisker. Examples of the plate-like filler include talc, mica, glass flake, and metal foil.
These fillers can be used singly or in combination of two or more. In addition, the said filler can also be used as a reinforcing material.
The blending amount of the filler is preferably 0 to 300 when the total amount of the polymer components including the acrylic rubber-reinforced vinyl resin [A1] and the (co) polymer [A2] is 100 parts by mass. Part by mass, more preferably 0 to 100 parts by mass.

Examples of the ultraviolet absorber include benzophenones, benzotriazoles, salicylic acid esters, metal complex salts and the like. These can be used alone or in combination of two or more.
The blending amount of the UV absorber is preferably 0 to 0 when the total amount of the polymer components including the acrylic rubber-reinforced vinyl resin [A1] and the (co) polymer [A2] is 100 parts by mass. It is 5 mass parts, More preferably, it is 0.01-3 mass parts.

Examples of the antioxidant include hindered amines, hydroquinones, hindered phenols, and sulfur-containing compounds. These can be used alone or in combination of two or more.
The amount of the antioxidant is preferably 0 to 0 when the total amount of the polymer components including the acrylic rubber-reinforced vinyl resin [A1] and the (co) polymer [A2] is 100 parts by mass. It is 5 mass parts, More preferably, it is 0.01-3 mass parts.

  Examples of the flame retardant include organic flame retardants, inorganic flame retardants, and reactive flame retardants. These can be used alone or in combination of two or more.

  In addition, when mix | blending a flame retardant with the molding material of this invention, it is preferable to use a flame retardant adjuvant together. As this flame retardant aid, antimony trioxide, antimony tetroxide, antimony pentoxide, sodium antimonate, antimony tartrate and other antimony compounds, zinc borate, barium metaborate, hydrated alumina, zirconium oxide, Examples thereof include ammonium polyphosphate, tin oxide, and iron oxide. These can be used alone or in combination of two or more.

The molding material of this invention can be manufactured by melt-kneading each component with an extruder, a Henschel mixer, a Banbury mixer, a kneader, a roll, a feeder ruder, etc. A preferable production method is a method using an extruder, a Henschel mixer, and a Banbury mixer. In the kneading, the components may be added together and then kneaded, or may be kneaded while being added in portions. In the latter case, an extruder, a Henschel mixer, a Banbury mixer and the like are suitable.
Moreover, after kneading with a Henschel mixer, a Banbury mixer, a kneader, etc., it can also be made into a predetermined shape such as pellets by an extruder.

The molding material of the present invention was prepared by conditioning a test piece having a length of 100 mm, a width of 30 mm and a thickness of 3 mm at a temperature of 23 ° C. and a relative humidity of 50% for 3 hours, and then heated under the following test conditions. 3 or less, preferably 2 or less, more preferably 1 or less, particularly preferably 0.
〔Test conditions〕
Hot plate temperature: 280 ° C
Traveling speed: 200 mm / second contact time of test piece and hot plate; 15 second melting amount of test piece; 0.5 mm.

  In addition, the molding material of the present invention has a deflection temperature under load (Under Load) measured according to ISO75, preferably 80 ° C. or higher, more preferably 81 ° C. or higher.

  Since the molding material of the present invention is excellent in fluidity at the time of melting, an injection molding method, a sheet extrusion molding method, a vacuum molding method, a profile extrusion molding method, a compression molding method, a hollow molding method, a differential pressure molding method, a blow molding method. The lamp housing can be easily formed into a predetermined shape by various known molding methods such as foam molding and gas injection molding. Examples of the lamp housing include a head lamp housing, an extension, a lamp housing for a vehicle (two-wheeled vehicle, four-wheeled vehicle, etc.) such as a high-mount stop lamp housing, a lamp housing for home appliances, and a lamp housing for measuring equipment.

The lamp housing manufactured using the molding material of the present invention has no unevenness on the surface and is excellent in smoothness, so even when a metal layer is provided without an undercoat treatment, there is no surface haze, Good luminance can be obtained. For example, an aluminum vapor-deposited film (thickness: 0.1 nm), HMDS (1, 1, 1, 3, 3) is formed on a plate-shaped molded article manufactured using the molding material of the present invention under the conditions described in the following examples. , 3-hexamethyldisilazane) are sequentially formed and the total reflectance is measured, it is preferably 80% or more, more preferably 85% or more.
Generally, as a lamp housing for a vehicle, a laminated product in which a film made of a metal such as aluminum is formed as described above.

The lamp housing obtained as described above is joined to a resin lens made of an acrylic resin, polycarbonate resin, or the like by a joining method such as a vibration welding method, a hot plate welding method, or a laser welding method to form a lamp. Can do.
The vibration welding method is a welding method using frictional heat, and specifically, an amplitude of 0.3 while pressing the bonding surfaces (or bonding portions) of the lamp housing and the resin lens with a predetermined pressure. A vibration of about ~ 2.0 mm and a frequency of about 50 to 110 MHz is applied, and the resin is melted and joined by the generated frictional heat. Joining by this method is usually performed by a vibration welding machine or the like.
The hot plate welding method is to apply a hot plate at a temperature of 220 to 300 ° C. between the joint surfaces (or joints) of the lamp housing and the resin lens to melt the resin on each joint surface (or joint). Thereafter, the hot plate is removed, and the two are immediately pressed to join them.
In addition, the laser welding method is a method in which each of the joining surfaces (or joints) of the lamp housing and the resin lens is overlapped, and then the laser light transmitting material is more transparent among the constituent materials of the lamp housing and the resin lens. By irradiating the outside of the high member with laser light, the laser light that has passed through the transparent material heats the contact surface of the other member to melt the material, and at the same time transmits the laser light by heat transfer. This is a method in which the material on the side is also melted and both are joined.

  As a method for joining the lamp housing and the resin lens manufactured using the molding material of the present invention, the vibration welding method and the hot plate welding method are suitable. According to the vibration welding method, it is possible to suppress the occurrence of resin powder, (thread) burrs, etc. around the joint. Also, according to the hot plate welding method, the heat type such as the hot plate and the constituent material of the housing Generation of stringing or the like can be suppressed in the meantime.

  Since the lamp obtained as described above has few defective phenomena at the joint portion, it has excellent appearance, and also has excellent impact resistance as an integrated object. In addition, since there are few defective phenomena, there is no need for post-processing, and thus the yield in manufacturing can be improved.

  EXAMPLES Hereinafter, although an example is given and this invention is demonstrated concretely, this invention is not restrict | limited at all by the following examples. In Examples, parts and% are based on mass unless otherwise specified.

1. Evaluation Methods Various evaluation methods used in this example are as follows.
(1) Melt flow rate It measured according to ASTM-D1238 (240 degreeC, 10 kg). The unit is g / 10 minutes.
(2) Charpy impact strength Measured according to ISO 179 (normal temperature). The unit is kJ / m ² .
(3) Deflection temperature under load Measured according to ISO75 (Under Load). The unit is ° C.

(4) Vibration weldability Pellets made of molding material are put into a molding machine (model name “IS-170FA”, manufactured by Toshiba Machine Co., Ltd.) and melted at a temperature of 220 to 260 ° C. to obtain a lamp housing of a predetermined shape. It was. On the other hand, using a methacrylic resin (trade name “Acrypet VH-4”, manufactured by Mitsubishi Rayon Co., Ltd.), it was melted at 220 to 270 ° C. to form a lens member. The lamp housing and the lens member are vibration welded under the following conditions by a vibration welding machine (model name “BURANSON 2407”, manufactured by Nippon Emerson), and the number of resin powders (generated in the lamp housing) The number of resin powders of several tens of microns to 2 mm that can be visually confirmed) and the number of thread burrs (the number of thread burrs of 2 mm or more generated in the lamp housing) were counted. “Vibration weldability” was evaluated based on the number of resin powders and the number of yarn burrs.
The judgment criteria are as follows.
○: The number of thread burrs was 5 or less.
X: The number of thread burrs was 6 or more.

<Vibration welding conditions>
The evaluation of the amount of powder was performed under the following conditions.
Half amplitude 0.5mm
Initial pressure 2.0 bar
Initial vibration time 4.0 seconds Second stage pressure 4.0 bar
Second stage vibration time 2.0 seconds.
The evaluation of the yarn burr amount was performed under the following conditions.
Half amplitude 0.5mm
Initial pressure 5.0 bar
Initial vibration time 0.5 seconds Second stage pressure 5.0 bar
Second stage vibration time 2.0 seconds.

(5) Hot plate weldability Pellets made of a molding material are put into a molding machine (model name “IS-25EP”, manufactured by Toshiba Machine Co., Ltd.), melted at a temperature of 220 to 250 ° C., 10 cm long and 3 cm wide. A hot plate welding test piece having a thickness of 3 mm was formed. The test piece was conditioned for 3 hours at a temperature of 23 ° C. and a relative humidity of 50%, and then brought into contact with the hot plate under the following conditions using a hot plate welding machine (manufactured by Techno Polymer Co.). When leaving, I counted the number of yarns. “Heat plate weldability” was evaluated based on the number of yarns.
The judgment criteria are as follows.
○: The number of stringing was 3 or less.
X: The number of stringing exceeded three.

<Hot plate welding conditions>
Hot plate temperature 280 ℃
Servo motor moving speed 200mm / second Time when test piece contacts hot plate 15 seconds Melting amount of test piece 0.5mm

(6) Luminance Sputtering is performed on the surface of the lamp housing obtained in the above vibration welding evaluation using a vacuum film forming apparatus (model name “VRSP350MD”, manufactured by Shin Meiwa Kogyo Co., Ltd.) under the following conditions, and an aluminum vapor deposition film: Formed. Thereafter, a plasma polymerized film of HMDS (1,1,1,3,3,3-hexamethyldisilazane) was formed on the surface of the deposited film under the following conditions.
The luminance was measured by irradiating light on the film surface of the lamp housing having the above laminated film with a digital reflectometer (model name “TR-1100AD”, manufactured by Tokyo Denshoku Co., Ltd.). Evaluation was made with reflectivity. The unit is%.

<Sputtering conditions>
Pressure after roughing 5.0 Pa
Pressure after completion of main pulling 5.0 × 10 ⁻³ Pa
Introduction gas Argon gas is 100 SCCM
Degree of vacuum during film formation 0.7 Pa
Aluminum film thickness 120nm
<Plasma polymerization conditions>
Introduced gas HMDS 30 SCCM
Degree of vacuum during polymerization 1.5 Pa

2. Production of Acrylic Rubber Reinforced Vinyl Resin [A1] The acrylic rubber reinforced vinyl resin [A1] was prepared by first preparing a latex containing an acrylic rubbery polymer, and then using the latex to produce by emulsion polymerization. .

Production Example 1 (Production of acrylic rubber-reinforced vinyl resin [A1-1])
The latex was prepared by a two-step polymerization.
In the first step, 10.0 parts of n-butyl acrylate, 0.02 part of allyl methacrylate, sodium dodecylbenzene sulfonate, and 1. are added to a reactor equipped with a reflux condenser, a stirring blade, a thermometer, and a temperature control device. 0 parts, 0.003 part of cumene hydroperoxide, 0.004 part of sodium ethylenediaminetetraacetate, 0.003 part of ferrous sulfate, 0.05 part of sodium formaldehyde sulfoxylate and 180 parts of ion-exchanged water were added and stirred. While the mixture was warmed. Thereafter, the temperature of the reaction system was set to 60 ° C., and polymerization was performed for 80 minutes. Next, while maintaining the temperature of the reaction system at 60 ° C., a mixture consisting of 25.0 parts of n-butyl acrylate, 0.05 part of allyl methacrylate and 0.006 part of cumene hydroperoxide was added over 90 minutes. Continuously added and polymerized. The polymerization conversion rate was 92%.
Subsequently, in the second step, 15.0 parts of n-butyl acrylate, 0.62 part of allyl methacrylate, and cumene hydropar were used, using the reaction solution from the first step as it was and maintaining the temperature of the reaction system at 60 ° C. A mixture of 0.004 parts of oxide was continuously added and polymerized over 90 minutes to obtain a latex (L1) containing an acrylic rubbery polymer. The polymerization conversion rate was 95%.
The acrylic rubbery polymer had a gel content of 63%, a volume average particle size of 110 nm, and a toluene swelling degree of 13.

Thereafter, in a reactor equipped with a reflux condenser, a stirring blade, a thermometer, and a temperature control device, 50 parts (solid content) of the latex (L1), 0.2 part of sodium dodecylbenzenesulfonate, and sodium formaldehyde sulfoxylate 0 15 parts were charged and the temperature of the mixture was 60 ° C. Subsequently, while maintaining the temperature of the reaction system at 60 ° C., a mixture (i) comprising 37.8 parts of styrene, 12.2 parts of acrylonitrile and 0.25 parts of tert-dodecyl mercaptan, and tert-butyl hydroperoxide 0 A mixture (ii) consisting of 2 parts, 0.6 parts of sodium dodecylbenzenesulfonate and 12 parts of ion-exchanged water was continuously added and polymerized over 5 hours. After completion of the addition, the mixture was left for 1 hour to obtain a latex containing an acrylic rubber-reinforced vinyl resin [A1-1]. The polymerization conversion rate was 95%.
The acrylic rubber-reinforced vinyl resin [A1-1] was isolated by adding calcium chloride to the latex, coagulating and filtering, and then washing and drying to obtain a powder. The graft rate was 66%.

Production Example 2 (Production of acrylic rubber-reinforced vinyl resin [A1-2])
The latex was prepared by a two-step polymerization.
In the first step, 10.0 parts of n-butyl acrylate, 0.005 parts of allyl methacrylate, sodium dodecylbenzenesulfonate, and 1. are added to a reactor equipped with a reflux condenser, a stirring blade, a thermometer, and a temperature control device. 0 parts, 0.003 part of cumene hydroperoxide, 0.004 part of sodium ethylenediaminetetraacetate, 0.003 part of ferrous sulfate, 0.05 part of sodium formaldehyde sulfoxylate and 180 parts of ion-exchanged water were added and stirred. While the mixture was warmed. Thereafter, the temperature of the reaction system was set to 60 ° C., and polymerization was performed for 80 minutes. Next, while maintaining the temperature of the reaction system at 60 ° C., a mixture consisting of 25.0 parts of n-butyl acrylate, 0.013 part of allyl methacrylate and 0.006 part of cumene hydroperoxide was mixed over 90 minutes. Continuously added and polymerized. The polymerization conversion was 91%.
Subsequently, in the second step, 15.0 parts of n-butyl acrylate, 0.62 part of allyl methacrylate, and cumene hydropar were used, using the reaction solution from the first step as it was and maintaining the temperature of the reaction system at 60 ° C. A mixture of 0.004 parts of oxide was continuously added and polymerized over 90 minutes to obtain latex (L2) containing an acrylic rubbery polymer. The polymerization conversion rate was 95%.
The acrylic rubbery polymer had a gel content of 58%, a volume average particle size of 105 nm, and a toluene swelling degree of 12.

Thereafter, 50 parts of the latex (L2) (solid content), 0.2 part of sodium dodecylbenzenesulfonate, and sodium formaldehyde sulfoxylate 0 were added to a reactor equipped with a reflux condenser, a stirring blade, a thermometer, and a temperature control device. 15 parts were charged and the temperature of the mixture was 60 ° C. Subsequently, while maintaining the temperature of the reaction system at 60 ° C., a mixture (i) comprising 37.8 parts of styrene, 12.2 parts of acrylonitrile and 0.25 parts of tert-dodecyl mercaptan, and tert-butyl hydroperoxide 0 A mixture (ii) consisting of 2 parts, 0.6 parts of sodium dodecylbenzenesulfonate and 12 parts of ion-exchanged water was continuously added and polymerized over 5 hours. After completion of the addition, the mixture was left for 1 hour to obtain a latex containing an acrylic rubber-reinforced vinyl resin [A1-2]. The polymerization conversion rate was 95%.
The acrylic rubber-reinforced vinyl resin [A1-2] was recovered in the same manner as in Production Example 1 and obtained as a powder. The graft rate was 62%.

Production Example 3 (Production of acrylic rubber-reinforced vinyl resin [A1-3])
The latex was prepared by a two-step polymerization.
In the first step, 10.0 parts of n-butyl acrylate, 0.5 parts of allyl methacrylate, sodium dodecylbenzenesulfonate, and 1. are added to a reactor equipped with a reflux condenser, a stirring blade, a thermometer, and a temperature control device. 0 parts, 0.003 part of cumene hydroperoxide, 0.004 part of sodium ethylenediaminetetraacetate, 0.003 part of ferrous sulfate, 0.05 part of sodium formaldehyde sulfoxylate and 180 parts of ion-exchanged water were added and stirred. While the mixture was warmed. Thereafter, the temperature of the reaction system was set to 60 ° C., and polymerization was performed for 80 minutes. Next, while maintaining the temperature of the reaction system at 60 ° C., a mixture consisting of 25.0 parts of n-butyl acrylate, 0.013 part of allyl methacrylate and 0.006 part of cumene hydroperoxide was mixed over 90 minutes. Continuously added and polymerized. The polymerization conversion was 91%.
Subsequently, in the second step, 15.0 parts of n-butyl acrylate, 0.62 part of allyl methacrylate, and cumene hydropar were used, using the reaction solution from the first step as it was and maintaining the temperature of the reaction system at 60 ° C. A mixture of 0.004 parts of oxide was continuously added and polymerized over 90 minutes to obtain latex (L3) containing an acrylic rubbery polymer. The polymerization conversion rate was 95%.
The acrylic rubbery polymer had a gel content of 80%, a volume average particle size of 100 nm, and a toluene swelling degree of 5.

Thereafter, 40 parts of the latex (L3) (solid content), 1 part of sodium dodecylbenzenesulfonate, and 150 parts of ion-exchanged water were charged into a reactor equipped with a reflux condenser, a stirring blade, a thermometer, and a temperature controller. After nitrogen substitution, 0.02 part of disodium ethylenediaminetetraacetate, 0.005 part of ferrous sulfate and 0.3 part of sodium formaldehydesulfoxylate were added, and the temperature was raised to 60 ° C. with stirring. On the other hand, 0.2 part of cumene hydroperoxide was dissolved in 60 parts of a mixture of acrylonitrile and styrene (mass ratio 25/75) and purged with nitrogen. While maintaining the temperature of the reaction system at 60 ° C., this monomer mixture is added to the reaction system at a constant flow rate for 3 hours using a metering pump, polymerization is performed, and acrylic rubber-reinforced vinyl resin [A1 -3] was obtained. The polymerization conversion rate was 97%.
The acrylic rubber-reinforced vinyl resin [A1-3] was recovered in the same manner as in Production Example 1 and obtained as a powder. The graft rate was 85%.

3. (Co) polymer [A2]
The following two types were used as the (co) polymer [A2].
3-1. Copolymer (A2-1)
It is a copolymer composed of 75% styrene units and 25% acrylonitrile units, and has an intrinsic viscosity [η] (measured in methyl ethyl ketone at 30 ° C.) of 0.6 dl / g.
3-2. Copolymer (A2-2)
The copolymer is composed of 70% α-methylstyrene units and 30% acrylonitrile units, and has an intrinsic viscosity [η] (measured in methyl ethyl ketone at 30 ° C.) of 0.4 dl / g.

4). Production and Evaluation of Molding Material for Lamp Housing Examples 1-2 and Comparative Example 1
Each of the components described above was added to a Henschel mixer at the mixing ratio shown in Table 1, and mixed for 3 minutes. Then, it melt-kneaded using the screw type | mold 40 mm diameter uniaxial extruder (cylinder setting temperature 220 degreeC), and obtained the pellet (molding material for lamp housings). Using this pellet, the above items were evaluated, and the results are shown in Table 1.

5. Effects of Examples Comparative Example 1 was an example in which the gel content of the acrylic rubbery polymer used for forming the acrylic rubber-reinforced vinyl resin was 70% or more, and was inferior in hot plate weldability.
On the other hand, Examples 1 and 2 were excellent in all of vibration weldability, hot plate weldability, and luminance.

  Since the molding material for the lamp housing of the present invention is excellent in fluidity at the time of melting, an injection molding method, a sheet extrusion molding method, a vacuum molding method, a profile extrusion molding method, a compression molding method, a hollow molding method, a differential pressure molding method, A lamp housing having a predetermined shape can be easily formed by various known molding methods such as blow molding, foam molding, and gas injection molding. Examples of the lamp housing include a head lamp housing, an extension, a lamp housing for a vehicle (two-wheeled vehicle, four-wheeled vehicle, etc.) such as a high-mount stop lamp housing, a lamp housing for home appliances, and a lamp housing for measuring equipment.

Claims (4)

An acrylic polymer obtained by polymerizing a vinyl monomer [b1] containing an aromatic vinyl compound and a vinyl cyanide compound in the presence of an acrylic rubbery polymer [a1] having a toluene gel content of less than 70%. For a lamp housing containing a rubber-reinforced vinyl resin [A1] or a mixture of the acrylic rubber-reinforced vinyl resin [A1] and a (co) polymer [A2] of a vinyl monomer [b2] A molding material,
The content of the acrylic rubber polymer [a1] is 5 to 40% by mass with respect to the total amount of the molding material for the lamp housing, and
A test piece of length 100 mm, width 30 mm and thickness 3 mm made of the molding material for the lamp housing was conditioned at a temperature of 23 ° C. and a relative humidity of 50% for 3 hours, and then heated under the following test conditions. A molding material for a lamp housing, characterized in that the number of stringing observed when brought into contact with a hot plate and separated from the hot plate is 3 or less.
〔Test conditions〕
Hot plate temperature: 280 ° C
Movement speed: 200 mm / second contact time of test piece and hot plate; 15 second melting amount of test piece; 0.5 mm The acrylic rubbery polymer [a1] is an acrylic acid alkyl ester (m1) having an alkyl group having 1 to 12 carbon atoms, a compound (m2) copolymerizable with the acrylic acid alkyl ester (m1), A copolymer obtained by copolymerizing a polyfunctional vinyl compound (m3), having a volume average particle diameter of 40 to 190 nm, and a toluene swelling degree of 6 to 20,
When the use ratio of the alkyl acrylate ester (m1) and the compound (m2) is 100% by mass, the content is 60 to 100% by mass and 0 to 40% by mass, respectively. The lamp according to claim 1, wherein the amount of the functional vinyl compound (m3) used is 0.1 to 10 parts by mass with respect to 100 parts by mass of the total amount of the alkyl acrylate ester (m1) and the compound (m2). Molding material for housing. The acrylic rubbery polymer [a1] is an alkyl acrylate ester (m11) having an alkyl group having 1 to 12 carbon atoms, a compound (m21) copolymerizable with the alkyl acrylate ester (m11), and A first step of copolymerizing the polyfunctional vinyl compound (m31) at a polymerization conversion rate of 85% or more;
In the presence of the copolymer obtained in the first step, an alkyl acrylate ester (m12) having an alkyl group having 1 to 12 carbon atoms, a compound copolymerizable with the alkyl acrylate ester (m12) (m22) And a second step of copolymerizing the polyfunctional vinyl compound (m32) at a polymerization conversion rate of 85% or more, and a polymer obtained from a method comprising:
The total amount of the acrylic acid alkyl ester (m11) and the compound (m21) used in the first step is the total of the acrylic acid alkyl esters (m11) and (m12) and the compounds (m21) and (m22). When the amount is 100% by mass, it is 50 to 90% by mass, and the usage amount of the polyfunctional vinyl compound (m31) is the total amount of the acrylic acid alkyl ester (m11) and the compound (m21) being 100. In the case of mass parts, it is 0.01 to 0.3 mass parts, and
The total amount of the acrylic acid alkyl ester (m12) and the compound (m22) used in the second step is the total of the acrylic acid alkyl esters (m11) and (m12) and the compounds (m21) and (m22). When the amount is 100% by mass, it is 10 to 50% by mass, and the amount of the polyfunctional vinyl compound (m32) used is 100 based on the total amount of the alkyl acrylate ester (m12) and the compound (m22). The molding material for a lamp housing according to claim 1, wherein the molding material is 0.5 to 10 parts by mass in terms of parts by mass.   The molding material for a lamp housing according to any one of claims 1 to 3, wherein a deflection temperature under load (Under Load) according to ISO75 is 80 ° C or higher.