JP2000276909A - Lamp body for vehicle luminaire, vehicle luminaire using it, and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent stringing of a resin material when a lens is welded regardless of the season and humidity and to improve quality by forming a lamp body with a resin composition blended with an antistatic agent at a specific ratio into a rubber-reinforced styrene resin of a specific ratio. SOLUTION: A lamp body 1 is formed with a resin composition blended with an antistatic agent such as alkane sulfone salt or alkylbenzene sulfonate at 0.1-5 pts.wt., preferably 0.5-4 pts.wt., into a rubber-reinforced styrene resin composition of 100 pts.wt. properly mixed with a graft copolymer containing a glycidyl ester compound of α,β-unsaturated acid as an essential component at 100-10 pts.wt. and a vinyl copolymer at 0-90 pts.wt. Stringing of the resin on a welded on surface, which is liable to occur when a hot plate is pressed to the surface 3 of the lamp body 1 to weld it and a lamp lens 4 is pressed, can be sharply improved even in a low-humidity environment in winter.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a headlamp, a turn signal lamp and a stop which are formed by joining a lamp body made of a rubber-reinforced styrene resin and a lamp lens made of a methyl methacrylate resin or the like by a hot plate fusion method. The present invention relates to a vehicular lamp such as a lamp, a lamp body used therefor, and a method of manufacturing the vehicular lamp.

[0002]

2. Description of the Related Art As a method of joining a lamp body made of a synthetic resin and a lamp lens, there is a method of fixing the both with an adhesive, but a general method of attaching a lamp plate made of a thermoplastic resin such as an ABS resin to a hot plate is used. After pressing and melting,
The so-called hot plate fusion method, in which the melted portion is pressed against a lamp lens made of methyl methacrylate resin, etc., is adopted from the viewpoint of environmental issues because no solvent is used at all unlike the case of fixing with an adhesive. Has increased.
However, in such a hot plate fusion method, the ABS
After the thermoplastic resin constituting the lamp body such as resin is melted by the hot plate, when the hot plate is separated, the melted resin is stretched in a thread shape (hereinafter referred to as "stringing"), and this is a lamp lens or a lamp. There was a case where a defect such as poor appearance was caused by adhering to the surface of the molded product of the body. As a method for improving the stringing in the hot plate fusion method, for example, Japanese Patent Application Laid-Open No. Hei 9-12902 discloses a method in which a fluorine resin such as polytetrafluoroethylene is used to form a thermoplastic resin such as polycarbonate or ABS resin constituting a lamp body. Has been proposed. However, in this method, when the hot plate fusion method is performed in a low humidity environment such as winter, stringing may not be completely eliminated.

[0003]

SUMMARY OF THE INVENTION In view of the above problems, the present inventors have constructed a lamp body for manufacturing a vehicle lamp by joining a lamp body to a lamp lens by a hot plate fusion method. An object of the present invention is to improve resin stringing irrespective of seasons and changes in humidity.

[0004]

Means for Solving the Problems The present inventors have conducted intensive studies to achieve the above-mentioned problems, and as a result, have formed a lamp body with a resin composition obtained by adding an antistatic agent to a rubber-reinforced styrene resin. Further, by using a resin composition obtained by blending a graft copolymer containing a specific component and a vinyl-based copolymer as the rubber-reinforced styrene-based resin, a low-humidity environment such as in winter. In the following, the present inventors have found that stringing when manufacturing a lamp for a vehicle by joining a lamp body and a lamp lens by a hot plate fusion method can be greatly improved, and have reached the present invention.

That is, according to the present invention, a heated hot plate is pressed against a lamp body made of a rubber-reinforced styrene-based resin and melted, and then the fused portion is pressed against a lamp lens to join the lamp body and the lamp lens to a vehicle. When manufacturing a lamp for a lamp, as the lamp body, a resin molded using a resin composition in which 0.1 to 5 parts by weight of an antistatic agent is blended with a rubber-reinforced styrenic resin is used. As the rubber-reinforced styrene-based resin, a resin composition containing, as a main component, a total of 100 parts by weight of 100 to 10 parts by weight of the following graft copolymer (A) and 0 to 90 parts by weight of the following vinyl copolymer (B) (C) is used. (A) 20 to 95 parts by weight of a rubbery polymer is mixed with a monomer mixture 8
By graft polymerization of 0 to 5 parts by weight, the monomer mixture is a vinyl cyanide compound, an aromatic vinyl compound,
And at least one vinyl compound 99.9 selected from the group consisting of alkyl and (meth) acrylate compounds
-60% by weight, other copolymerizable vinyl compounds 0-30
A graft copolymer containing 0.1% to 40% by weight of a glycidyl ester compound of an α, β-unsaturated acid. (B) A vinyl copolymer obtained by reacting 10 to 40% by weight of a vinyl cyanide compound, 60 to 90% by weight of an aromatic vinyl compound, and 0 to 30% by weight of another copolymerizable vinyl compound.

[0006]

It is particularly important in the present invention that an antistatic agent is incorporated in a resin composition used for molding a lamp body. As an antistatic agent, usually AB
What is necessary is just to be used for S resin, and it does not specifically limit. For example, a cationic surfactant such as an alkylamine salt, a sulfate of a higher alcohol, a sulfate of an ethylene oxide adduct of a higher alcohol, a sulfate of an ethylene oxide adduct of an alkylphenol, an alkane sulfonate, and an alkylbenzene sulfonate Anionic surfactants such as salts, alkylsulfosuccinates, salts of formalin condensates of naphthalenesulfonic acid, phosphates of ethylene oxide adducts of higher alcohols, phosphates of ethylene oxide adducts of alkylphenols, and sorbitans of higher fatty acids Ester, monoglycerin ester of higher fatty acid, ethylene oxide adduct of monoglycerin ester of higher fatty acid, ethylene oxide adduct of higher alcohol, ethylene oxide adduct of higher fatty acid, alkylphenol ethylene oxide Nonionic surfactants such as additives, amide ethylene oxide adducts, and ethylene oxide adducts of alkylamines; polyalkylene glycols, polyalkylene glycol-based copolymers, and polyetheresteramides. The above can be used. Among these, alkanesulfonates, alkylbenzenesulfonates, polyalkylene glycols and polyalkyleneglycol-based copolymers, and polyetheresteramides are preferred, and are particularly selected from the group consisting of alkanesulfonates and alkylbenzenesulfonates. The at least one antistatic agent used is particularly preferred.

The carbon number of the alkane or alkyl of the alkane sulfonate or alkylbenzene sulfonate is not particularly limited, but is preferably 6 to 29, more preferably 8 to 18 carbon atoms. Further, the number of sulfonic acid groups per molecule is not particularly limited, but the number of sulfonic acid groups is preferably 1 to 3. If the number of carbon atoms and the number of sulfonic acid groups are outside the above ranges, the impact strength tends to decrease. Examples of the salt include a sodium salt, a potassium salt, a lithium salt, a calcium salt, a magnesium salt and the like, and a sodium salt and a potassium salt are particularly preferable. These may be used alone or in combination of two or more.

The amount of the antistatic agent used is 0.1 to 5 parts by weight, preferably 0.5 to 4 parts by weight, based on 100 parts by weight of the rubber-reinforced styrene resin. If the amount is less than 0.1 part by weight, the effect of improving the stringing property particularly under low humidity is not sufficient.

The rubber-reinforced styrenic resin used in the present invention includes ABS resin, AAS resin, AES resin and the like. In particular, graft copolymer (A) 100 to 10
A resin composition (C) having a total of 100 parts by weight of a total of 100 parts by weight of the vinyl copolymer (B) and 0 to 90 parts by weight as the main component is preferable, and the graft copolymer (A) is shown below. Composition is preferred. That is, the graft copolymer (A)
Is obtained by adding the monomer mixture 80 to 20 to 95 parts by weight of the rubbery polymer.
When graft polymerizing the glycidyl ester compound of an α, β-unsaturated acid in an amount of from 0.1 to 40% by weight, more preferably from 0.5 to 30% by weight, and particularly preferably from 5 to 5% by weight.
20 wt% as an essential component, at least one vinyl compound selected from the group consisting of a vinyl cyanide compound, an aromatic vinyl compound, and an alkyl (meth) acrylate compound in an amount of 99.9 to 60 wt%, more preferably A vinyl compound consisting of 0 to 40% by weight of a vinyl cyanide compound, 60 to 90% by weight of an aromatic vinyl compound, and 0 to 30% by weight of an alkyl (meth) acrylate compound.
9-60% by weight, and 0 other copolymerizable vinyl compounds
It is a graft copolymer obtained by reacting about 30% by weight. Examples of the vinyl copolymer (B) include 10 to 40% by weight of a vinyl cyanide compound and 60 to 90% of an aromatic vinyl compound.
%, And a vinyl copolymer obtained by reacting 0 to 30% by weight of another copolymerizable vinyl compound. In the graft copolymer (A), the rubbery polymer is 2
If the amount is less than 0 parts by weight, the impact strength of the lamp body is reduced. Further, when the glycidyl ester compound of the α, β-unsaturated acid in the monomer mixture to be graft-polymerized to the rubber-like polymer is less than 0.1% by weight, it is not enough to join the lamp lens by the hot plate fusion method. When the amount exceeds 40% by weight, the fluidity of the resin during molding of the lamp body and the impact resistance of the molded lamp body are undesirably reduced.

The rubbery polymer used in the graft copolymer (A) is not particularly limited, but may be polybutadiene rubber, styrene-butadiene rubber (SBR), acrylonitrile-butadiene rubber (NBR), butyl acrylate butadiene. Diene rubber, butyl acrylate rubber, butadiene-butyl acrylate rubber, 2-ethylhexyl acrylate-butyl acrylate rubber, 2-ethylhexyl methacrylate-butyl acrylate rubber, stearyl acrylate-butyl acrylate rubber, dimethylsiloxane-butyl acrylate rubber Acrylic rubber such as silicone / butyl acrylate composite rubber, ethylene-
Examples thereof include polyolefin-based rubber polymers such as propylene rubber and ethylene-propylene-diene rubber, and silicone-based rubber polymers such as polydimethylsiloxane rubber, and these can be used alone or in combination of two or more.

The average particle size of the rubbery polymer is preferably 0.05 to 1 μm, and 0.07 to 0.4 μm.
μm is more preferred. As the rubbery polymer, those produced by an agglomeration enlargement method using an acid group-containing latex can also be used.

Α, which is graft-polymerized to the rubbery polymer,
Examples of the glycidyl ester compound of β-unsaturated acid include glycidyl acrylate, glycidyl methacrylate, glycidyl ethacrylate, and the like, and they can be used alone or in combination of two or more. Specific examples of preferred glycidyl ester compounds include glycidyl methacrylate.

Examples of the vinyl cyanide compound used in the graft copolymer (A) and the vinyl copolymer (B) include acrylonitrile, methacrylonitrile and the like. Examples of the aromatic vinyl compound include styrene, Examples thereof include α-methylstyrene, p-methylstyrene, p-isopropylstyrene, chlorostyrene, bromostyrene and the like. Examples of the alkyl (meth) acrylate compound include methyl (meth) acrylate, ethyl (meth) acrylate, and butyl (meth) acrylate. Further, as other copolymerizable vinyl compounds, acrylic acid, methacrylic acid, for example, maleimide compounds such as N-phenylmaleimide, vinyl acetate, ethyl vinyl ether, and the like, may be used alone or in combination of two or more. Can be.

The above graft copolymer (A) and vinyl copolymer (B) are preferably obtained by emulsion polymerization, but may be produced by any polymerization method. For example, known bulk polymerization, solution polymerization, suspension polymerization,
Any polymer produced by any polymerization method such as an emulsion-suspension polymerization method or an emulsion-bulk polymerization method may be used as long as the composition can be controlled within the range intended by the present invention. For example, the graft copolymer (A)
In the case of, the monomer mixture in the presence of a rubbery polymer,
What is necessary is just to polymerize with a radical initiator in an aqueous medium. At that time, the monomer mixture to be graft-polymerized may be used as a mixture or, if necessary, dividedly. Further, as a method of adding the monomer mixture,
The whole amount may be charged at once or may be added sequentially, and there is no particular limitation.

As the radical initiator, known initiators such as a thermal decomposition initiator such as potassium persulfate and a redox initiator such as Fe-reducing agent-organic peroxide can be used. In addition, a polymerization accelerator, a polymerization degree regulator, and an emulsifier can be appropriately selected and used. The polymerization temperature is preferably from 30 to 90C.

The blend ratio between the graft copolymer (A) and the vinyl copolymer (B) in the resin composition constituting the lamp body of the present invention is appropriately determined in order to obtain desired physical properties. It is good, but the graft copolymer (A)
Is 100 to 10 parts by weight, preferably 60 to 10 parts by weight,
The amount of the vinyl copolymer (B) is 0 to 90 parts by weight, preferably 40 to 90 parts by weight. It is also possible to polymerize the vinyl copolymer (B) in the same reactor after polymerizing the graft copolymer (A).

The intrinsic viscosity of the resin composition (C) containing the above graft copolymer (A) and vinyl copolymer (B) as main components is 0.25 to 1.
5 (dl / g) (N, N-dimethylformamide solution,
30 ° C.) is preferred.

The method for obtaining the resin composition (C) from the latex of the graft copolymer (A) or the vinyl copolymer (B) may be a known method. For example, it is obtained by coagulation with an inorganic salt such as calcium chloride, magnesium chloride or ammonium sulfate or an acid such as hydrochloric acid, sulfuric acid, phosphoric acid or acetic acid. Also, if necessary, when blending a resin, using a general method, for example, a blender such as a Henschel mixer or a ribbon blender, a desired stabilizer, an antioxidant, an ultraviolet absorber, a lubricant, a pigment, an inorganic filler, Glass fibers can be used as needed. In particular, phenol-based, sulfur-based, phosphorus-based, hindered amine-based stabilizers, antioxidants, benzophenone-based, benzotriazole-based ultraviolet absorbers used in styrene-based resins, and organopolysiloxanes, ethylenebisstearic acid amides, and fats Lubricants such as aromatic hydrocarbons, esters of higher fatty acids and higher alcohols, and the like can be used as molding resins for higher performance. These stabilizers,
The lubricants can be used alone or in combination of two or more.

Further, the resin composition (C) constituting the lamp body may include, in addition to the above graft copolymer (A) and vinyl copolymer (B), ordinary ABS resin, AS resin, polycarbonate resin, It can be used by blending with polyvinyl chloride resin, polyamide resin, PET resin, and PBT resin.

In the present invention, after a heated hot plate is pressed against a lamp body molded from a rubber-reinforced styrene resin such as the resin composition (C) as described above to melt it, the molten portion is pressed against a lamp lens. Then, the lamp body and the lamp lens are joined to manufacture a vehicular lamp. The temperature of the hot plate in the above case is preferably heated to 250 to 500 ° C. Further, it is preferable to use a lens made of methyl methacrylate resin as the lamp lens to be joined to the lamp body.

[0021]

The present invention will be described below in more detail with reference to examples, but these examples do not limit the present invention in any way. In the description of the examples, unless otherwise specified.
“Parts” represents parts by weight, and “%” represents weight%.

(A) Production of graft copolymer (A) The following substances were charged into a reactor equipped with a stirrer, a reflux condenser, a nitrogen inlet, a monomer inlet, and a thermometer. Pure water 250 parts Rubbery polymer Type and amount described in Table 1 Sodium formaldehyde sulfoxylate 0.3 parts Ferrous sulfate 0.0025 parts Disodium ethylenediaminetetraacetate 0.01 parts Nitrogen stream while stirring the reactor The temperature was raised to 60 ° C. below. After the temperature reached 60 ° C., the monomer mixture shown in Table 1 was continuously added dropwise over 5 hours.
Stirring was continued for another hour to complete the polymerization.

[0023]

[Table 1]

(B) Production of vinyl copolymer (B) The following substances were charged into a reactor equipped with a stirrer, a reflux condenser, a nitrogen inlet, a monomer inlet, and a thermometer. Pure water 250 parts Sodium laurate 3 parts Sodium formaldehyde sulfoxylate 0.4 parts Ferrous sulfate 0.0025 parts Disodium ethylenediaminetetraacetate 0.01 parts The temperature is raised to 60 ° C under a nitrogen stream while stirring the reactor. I let it. After reaching 60 ° C., the monomers (I) shown in Table 2 were charged. After sufficient emulsification, the monomers (I
I) was continuously added dropwise over 6 hours, and after the addition was completed, stirring was continued at 60 ° C. for 1 hour to complete the polymerization.

[0025]

[Table 2]

(C) Production of Lamp Body Resin Composition (C) for Vehicle Lighting and Evaluation of Stringing Property Graft copolymer (A) produced in (A) and (B) above
And the vinyl copolymer (B) were mixed in the latex state at the ratio (solid content) shown in Table 3, an antioxidant was added to the mixed latex, and the mixture was coagulated with calcium chloride, and then heated and dehydrated. After washing with water and drying, the obtained powder was treated with a phenolic antioxidant (AO-20: manufactured by Asahi Denka Kogyo Co., Ltd., 0.3 part) and a phosphorus stabilizer (PEP-24).
G: 0.3 parts by Asahi Denka Kogyo Co., Ltd.), lubricant EBS
(Ethylene bisstearic acid amide 1.0 part) as a common additive, and an antistatic agent (sodium tetradecanesulfonate or sodium dodecylbenzenesulfonate) as shown in Table 3 and blended at a temperature of 250 ° C. And pellets were obtained with an extruder (40 mmφ single screw extruder, manufactured by Osaka Seiki Co., Ltd.). 150 tons of pellets obtained
Using an ON injection molding machine (manufactured by FANUC), the ASTM No. 1 dumbbell and the lamp body product shown in FIG. 1 were molded at a temperature of 250 ° C., and the following stringiness was evaluated using the molded product. Are shown in Table 3.

(D) Evaluation of stringiness using a dumbbell test piece An ASTM No. 1 dumbbell obtained by injection molding was left immediately after molding under an environment under the following conditions. Conditions: Left for one week in a constant temperature room at 23 ° C. and 50% relative humidity. Condition: Assuming low humidity in winter, leave in a constant temperature room at 5 ° C. and 15% RH for 1 week. Using this test piece, it was pressed against an aluminum flat plate heated to 320 ° C. at a pressure of 10 kgf / cm ² for 10 seconds, and the dumbbell was pulled up at a speed of 500 mm / min. The length [cm] was measured.

(E) Evaluation of stringiness using lamp body product The lamp body product shown in FIG. 1 obtained by injection molding was left immediately after molding in an environment under the following conditions. Conditions: Left for one week in a constant temperature room at 23 ° C. and 50% relative humidity. Condition: Assuming low humidity in winter, leave in a constant temperature room at 5 ° C. and 15% RH for 1 week. This product was fused using a hot plate fusion machine at a fusion temperature of 320 ° C and 1
0 kgf / cm ^{2 at} a pressure of 10
After pressing for 2 seconds, it was determined whether or not stringing occurred on the fused surface when pulled up at a speed of 50 mm / min.

[0029]

[Table 3]

As is evident from the results in Table 3, even when the lamp body was conditioned under low humidity, according to the present invention, the case where the lamp body made of the ABS resin composition of the comparative example conventionally used was used. In comparison with the above, the stringiness in the hot plate fusion method is greatly improved.

[0031]

According to the present invention, by using a rubber-reinforced styrene resin mixed with an antistatic agent, a general rubber-reinforced styrene resin conventionally used as a material for a lamp body can be used. Compared to the case, for example, in a low humidity environment such as winter, after a heated hot plate is pressed against the lamp body and melted, the fused portion is pressed against the lamp lens to join the lamp body and the lamp lens. The present invention can greatly improve stringing of a resin constituting a lamp body when manufacturing a vehicle lamp, and is particularly useful for manufacturing a vehicle lamp such as a head lamp, a blinker, and a stop lamp.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a lamp body product used for evaluating stringiness.

[Explanation of symbols]

1: lamp body, 2: lamp, 3: fused surface, 4: lamp lens

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (Reference) C08L 71/02 C08L 77/12 77/12

Claims (19)

[Claims] After a heated hot plate is pressed against a lamp body made of a rubber-reinforced styrene resin and melted, the fused portion is pressed against a lamp lens to join the lamp body and the lamp lens to form a vehicle lamp. What is claimed is: 1. A lamp body for manufacturing, comprising: a resin composition obtained by mixing 0.1 to 5 parts by weight of an antistatic agent with 100 parts by weight of a rubber-reinforced styrene resin. 2. The method according to claim 1, wherein the antistatic agent is an alkane sulfonate, an alkylbenzene sulfonate, a polyalkylene glycol, a polyalkylene glycol-based copolymer,
2. The lamp body for a vehicle lighting device according to claim 1, wherein the lamp body is at least one selected from the group consisting of: and a polyetheresteramide. 3. The lamp body according to claim 1, wherein the antistatic agent is at least one selected from the group consisting of alkane sulfonates and alkylbenzene sulfonates. 4. The rubber-reinforced styrenic resin is mainly composed of 100 to 10 parts by weight of the following graft copolymer (A) and 0 to 90 parts by weight of the following vinyl copolymer (B) as a main component. The lamp body for a vehicle lamp according to any one of claims 1 to 3, which is a resin composition (C). (A) 20 to 95 parts by weight of a rubbery polymer is mixed with a monomer mixture 8
By graft polymerization of 0 to 5 parts by weight, the monomer mixture is a vinyl cyanide compound, an aromatic vinyl compound,
And at least one vinyl compound 99.9 selected from the group consisting of alkyl and (meth) acrylate compounds
-60% by weight, other copolymerizable vinyl compounds 0-30
A graft copolymer comprising 0.1% to 40% by weight of a glycidyl ester compound of an α, β-unsaturated acid; (B) A vinyl copolymer obtained by reacting 10 to 40% by weight of a vinyl cyanide compound, 60 to 90% by weight of an aromatic vinyl compound, and 0 to 30% by weight of another copolymerizable vinyl compound. 5. The monomer mixture of the graft copolymer (A) comprises 0 to 40% by weight of a vinyl cyanide compound, 60 to 90% by weight of an aromatic vinyl compound, and alkyl (meth).
99.9 to 60% by weight of a vinyl compound composed of 0 to 30% by weight of an acrylate compound, 0 to 30% by weight of another copolymerizable vinyl compound, and 0.1 of a glycidyl ester compound of an α, β-unsaturated acid The lamp body for a vehicle lighting device according to claim 4, which comprises about 40% by weight. 6. The glycidyl ester compound content in the monomer mixture of the graft copolymer (A) is 5 to 20.
The lamp body for a vehicle lamp according to claim 4, wherein the weight is% by weight. 7. The vehicle lamp according to claim 4, wherein the glycidyl ester compound is at least one selected from the group consisting of glycidyl acrylate, glycidyl methacrylate, and glycidyl ethacrylate. body. 8. The lamp body for a vehicle lamp according to claim 4, wherein the glycidyl ester compound is glycidyl methacrylate. 9. The rubber-like polymer having an average particle size of 0.0
The lamp body for a vehicle lamp according to any one of claims 4 to 8, wherein the thickness is 5 to 1 µm. 10. The rubbery polymer is a polybutadiene rubber, a styrene-butadiene rubber, an acrylonitrile-
Butadiene rubber, butyl acrylate butadiene rubber, butyl acrylate rubber, butadiene-butyl acrylate rubber, 2-ethylhexyl acrylate-butyl acrylate rubber, 2-ethylhexyl methacrylate-butyl acrylate rubber, stearyl acrylate-butyl acrylate rubber, dimethylsiloxane- 10. At least one selected from the group consisting of butyl acrylate rubber, silicone-based / butyl acrylate composite rubber, ethylene-propylene rubber, ethylene-propylene-diene rubber, and polydimethylsiloxane. Lamp body for vehicle lighting. 11. The lamp body for a vehicle lamp according to claim 4, wherein the vinyl cyanide compound is at least one of acrylonitrile and methacrylonitrile. 12. The aromatic vinyl compound is at least one selected from the group consisting of styrene, α-methylstyrene, p-methylstyrene, p-isopropylstyrene, chlorostyrene, and bromostyrene. 12. The lamp body for vehicle lighting according to any one of claims 11 to 11. 13. The alkyl (meth) acrylate compound is methyl (meth) acrylate, ethyl (meth)
13. At least one selected from the group consisting of acrylate and butyl (meth) acrylate.
A lamp body for a vehicle lighting device according to any one of the above. 14. The method according to claim 4, wherein the other copolymerizable vinyl compound is at least one selected from the group consisting of acrylic acid, methacrylic acid, N-phenylmaleimide, vinyl acetate and ethyl vinyl ether. A lamp body for a vehicle lighting device according to any one of the claims. 15. After the heated hot plate is pressed against the lamp body according to any one of claims 1 to 14 and melted, the fused portion is pressed against the lamp lens to join the lamp body and the lamp lens. A method for manufacturing a vehicular lamp, comprising: 16. The method for manufacturing a vehicular lamp according to claim 15, wherein the heating is performed by heating the hot plate to 250 to 500 ° C. 17. The method for manufacturing a vehicular lamp according to claim 15, wherein a lens made of methyl methacrylate resin is used as the lamp lens. 18. The lamp body according to claim 1, wherein the heated hot plate is pressed and melted, and then the fused portion is pressed against a lamp lens to join the lamp body and the lamp lens. Vehicle lighting. 19. The lens according to claim 18, wherein the lamp lens is a lens made of methyl methacrylate resin.
The vehicle lighting device as described in the above.