HOUSING PART FOR VEHICLE CAMERA AND METHOD FOR ITS MANUFACTURING

Abstract

A housing part for a vehicle camera, obtained by injection molding a resin composition comprising 100 to 300 parts by mass of a fibrous inorganic filler and a non-fibrous inorganic filler to 100 parts by mass of a polyarylene sulfide resin and having an elastomer content of 10% by mass or less, wherein the polyarylene sulfide resin has a melt viscosity of 70 Pa·s or less, measured at a temperature of 310 °C and a shear rate of 1200 s⁻¹, and wherein the mass ratio of the fibrous inorganic filler to the non-fibrous inorganic filler is 0.2 to 4.5, and which satisfies the following conditions (A) and (B): (A) when a molded part of 80 mm × 80 mm × 1 mm is produced using the resin composition under conditions of a cylinder temperature of 320 °C, a mold temperature of 140 °C and a holding pressure of 70 MPa injection molded,an absolute value of (shrinkage rate in one direction perpendicular to a flow direction) - (shrinkage rate in the flow direction) is 0.5% or less; and (B) the water absorption rate of a molded part measuring 80 mm × 80 mm × 2 mm, injection molded using the resin composition under conditions of a cylinder temperature of 320°C, a mold temperature of 140°C and a holding pressure of 70 MPa, is 0.3% or less when subjected to a hot water immersion test at 80°C for 300 hours.

Description

TECHNICAL AREA

[0001] The present invention relates to a housing part for a vehicle camera, which can be used as a housing or as a lens tube of the vehicle camera. TECHNICAL BACKGROUND

[0002] In recent years, onboard cameras, which are mounted on or near windshields or rear windows of vehicles such as cars and trucks and capture images of the front or rear of the vehicle through the windshield or rear window, have become widespread. Unlike conventional cameras, onboard cameras are permanently installed in the vehicle or are exposed to vibrations, high temperatures, and high humidity, especially in summer, while driving. Therefore, measures must be taken to maintain their performance.

[0003] Resin is frequently used as a material for housing components, such as the housing and lens tube, that are part of a vehicle camera. The occurrence of warping in the housing must be minimal. Furthermore, the lens tube must have high roundness to hold the lens securely and maintain optical performance. As described above, high temperatures and humidity prevail inside a vehicle, especially in summer. In such an environment, the housing tends to deform, and the lens tube is prone to losing its roundness. Even a slight decrease in the lens tube's roundness can lead to misalignment of the optical axis and impair optical performance. This means that both the housing and the lens tube must have dimensional accuracy to maintain their original dimensions with minimal deformation, even under high temperatures and humidity.In particular, the lens tube must have extremely precise dimensional accuracy, as even a small misalignment of the lens impairs the optical performance as described above.

[0004] Polyarylene sulfide resins (hereinafter referred to as "PAS resins"), represented by polyphenylene sulfide resins (hereinafter referred to as "PPS resins"), exhibit high heat resistance, mechanical properties, chemical resistance, dimensional stability, and flame retardancy, and are widely used in materials for electrical and electronic device components, automotive components, chemical device components, and the like. Therefore, PAS resins are useful as a material for a housing part of a vehicle camera. Molded products made from PAS resin have been proposed to increase roundness and prevent warping (increase flatness) (see patent literature 1 to 3).

[0005] In contrast, the lens tube can be assembled by pressing a lens into the lens tube during the manufacturing process. In this case, it is advantageous to use a material with high toughness for the lens tube to prevent cracking and similar defects due to the press fit. However, when using a composition with an inorganic filler added to the PAS resin, toughness alone may be insufficient, and therefore, adding an elastomer to the composition to improve toughness is being considered. QUOTE LIST PATENT LITERATURE Patent Literature 1: Japanese Unexamined Patent Application Publication No. 2007-204615 Patent Literature 2: Japanese Unexamined Patent Application Publication No. 2007-204616 Patent Literature 3: Japanese Unexamined Patent Application Publication No. 2009-173865 SUMMARY OF THE INVENTIONAL PROBLEM

[0006] The inventions described in patent specifications 1 to 3 do not take into account a housing component of a vehicle camera. That is, they do not consider use in environments with large temperature and humidity fluctuations and high temperatures and humidity (hereinafter referred to as "high temperature and humidity environments"), such as in a vehicle interior, particularly in a vehicle cabin (windshield side or rear window side) and in a front grille near an engine compartment where a vehicle camera is installed. Therefore, it is not always possible to reduce the occurrence of warping and maintain high roundness even in such an environment. Furthermore, when a lens is pressed in and mounted during manufacturing, the lens barrel must be robust enough to prevent breakage during pressing and to maintain dimensional accuracy both during pressing and during use.When an elastomer is used to improve toughness, its water absorption may increase, or gases may form if the elastomer is used in a high-temperature, high-humidity environment. Increased water absorption degrades dimensional accuracy, and gas formation leads to lens fogging.

[0007] The present invention was made in consideration of the problems described above. One objective of the present invention is to provide a housing component for a vehicle camera that exhibits excellent dimensional accuracy and holding power even at high temperatures and high humidity, and in which gas formation is prevented. TECHNICAL SOLUTION

[0008] In response to the problems mentioned above, one or more aspects of the present invention are directed towards: (1) Housing part for a vehicle camera obtained by injection molding of a resin composition comprising 100 to 300 parts by mass of a total quantity of a fibrous inorganic filler and a non-fibrous inorganic filler comprising 100 parts by mass of a polyarylene sulfide resin and having an elastomer content of 10 percent by mass or less, and which meets the following conditions (A) and (B). (A) When a molded part measuring 80 mm × 80 mm × 1 mm is injection molded using the resin composition under conditions of a cylinder temperature of 320 °C, a mold temperature of 140 °C and a holding pressure of 70 MPa, the absolute value of (shrinkage rate in a direction perpendicular to the flow direction) - (shrinkage rate in the flow direction) is 0.5% or less. (B) The water absorption rate of a molded part measuring 80 mm × 80 mm × 2 mm, injection molded using the resin composition under conditions of a cylinder temperature of 320 °C, a mold temperature of 140 °C and a holding pressure of 70 MPa, is 0.3% or less when subjected to a hot water immersion test at 80 °C for 300 hours. (2) The housing part for the vehicle camera according to (1), wherein the polyarylene sulfide resin has a melt viscosity of 70 Pa-s or less, measured at a temperature of 310 °C and a shear rate of 1200 s -1 . (3) The housing part for the vehicle camera according to (1) or (2), wherein the mass ratio of the fibrous inorganic filler to the non-fibrous inorganic filler is 0.2 to 4.5. (4) The housing part for the vehicle camera according to one of points (1) to (3), wherein an average value of a linear expansion coefficient in one flow direction and a linear expansion coefficient in a direction perpendicular to the flow direction at 150 °C 35 (× 10 -6 K -1 ) or less. (5) The housing part for the vehicle camera according to any one of points (1) to (4), wherein the amount of creep deformation when a stress of 67 MPa is applied for 500 hours at a temperature of 120 °C is 3 mm or less. (6) The housing part for a vehicle camera according to any of points (1) to (5), wherein the housing part is used in a vehicle camera which is mounted in a front grille of a vehicle or in a position facing a windscreen. (7) The housing part for the vehicle camera according to any one of points (1) to (6), wherein the housing part is a lens tube to support and hold a lens in the vehicle camera in a press-fit condition. (8) The housing part for the vehicle camera according to any one of points (1) to (6), wherein the housing part is a housing that forms an outer surface of the vehicle camera. ADVANTAGEOUS EFFECTS

[0009] The present invention makes it possible to provide a housing part for a vehicle camera that exhibits excellent dimensional accuracy and holding performance even at high temperatures and high humidity, and in which gas formation is prevented. List of characters [ Fig. 1] Fig. Figure 1 is a top view of an injection-molded test specimen for measuring a linear expansion coefficient in examples and comparative examples. [ Fig. 2] Fig.Figure 2 shows (A) a top view and (B) a side view of a molded part used in an interference fit test in examples and comparison examples. DESCRIPTION OF THE EXECUTION FORMS

[0010] A housing component for a vehicle camera according to the present embodiment is produced by molding a resin composition containing 100 to 300 parts by mass of a fibrous inorganic filler and a non-fibrous inorganic filler, totaling 100 parts by mass of a PAS resin, and having an elastomer content of 10 percent by mass or less. Then the following conditions (A) and (B) are satisfied: (A) when a molded part measuring 80 mm × 80 mm × 1 mm is injection molded using the resin composition under conditions of a cylinder temperature of 320 °C, a mold temperature of 120 °C and a holding pressure of 70 MPa, an absolute value of (shrinkage rate in one direction perpendicular to a flow direction) - (shrinkage rate in the flow direction) is 0.5% or less; and (B) the water absorption rate of a molded part measuring 80 mm × 80 mm × 2 mm, injection molded using the resin composition under conditions of a cylinder temperature of 320 °C, a mold temperature of 120 °C and a holding pressure of 70 MPa, is 0.3% or less when subjected to a hot water immersion test at 80 °C for 300 hours.

[0011] Since the housing part for the vehicle camera according to the present embodiment contains a predetermined amount of the fibrous inorganic filler and the non-fibrous inorganic filler, the housing part not only has high mechanical strength but also a low water absorption rate to the extent that condition (B) is fulfilled. Thus, the dimensional accuracy is excellent to the extent that condition (A) is fulfilled in an environment with high temperature and high humidity. The housing part for the vehicle camera according to the present embodiment is suitably attached to a housing that forms the outer surface of the vehicle camera or to a lens tube that accommodates a lens in the vehicle camera and holds it in a press-fit condition.In both cases, when applied to the housing and the lens tube, high dimensional accuracy is maintained even under high temperature and humidity conditions. In particular, it is possible to maintain good dimensional accuracy in a vehicle with high temperatures and humidity during the summer. The housing component for the vehicle camera according to the present embodiment is especially beneficial for the lens tube, since even a slight deviation in dimensions, particularly in the lens tube, impairs optical performance.

[0012] Since the present embodiment does not contain an elastomer that can cause the formation of gas, or even if it does, it is very small, the water absorption capacity is not increased, and it is possible to prevent the lens from fogging due to gas originating from the elastomer.

[0013] It should be noted that the vehicle camera is generally mounted in a vehicle's front grille, on the side of the windshield, or on a rear glass panel of the vehicle interior, and the temperature in the front grille and on the windshield side tends to be particularly high. Therefore, in the present embodiment, it is especially effective to use the vehicle camera mounted in the vehicle's front grille or in a position opposite the windshield.

[0014] Each component of the resin composition according to the present embodiment is described below. [Polyarylene sulfide resin]

[0015] A PAS resin has excellent mechanical properties, electrical properties, heat resistance, and other physical and chemical properties, dimensional stability, and good processability. The PAS resin is a polymer compound consisting mainly of -(Ar-S)- (where Ar is an arylene group) as a repeating unit, and a PAS resin with a generally known molecular structure is usable in the present embodiment.

[0016] Examples of the arylene group described above include a p-phenylene group, an m-phenylene group, an o-phenylene group, a substituted phenylene group, a p,p'-diphenylenesulfone group, a p,p'-biphenylene group, a p,p'-diphenylene ether group, a p,p'-diphenylene carbonyl group, and a naphthalene group. The PAS resin can be a homopolymer consisting only of the repeating unit described above. In some cases, a copolymer containing the following different repeating units may be preferable from a processability standpoint.

[0017] A polyphenylene sulfide resin with a p-phenylene sulfide group, which uses a p-phenylene group as the arylene group, is preferably used as the homopolymer. A combination of two or more different types of arylene sulfide groups from the arylene group described above can be used as the copolymer, with a combination containing a p-phenylene sulfide group and an m-phenylene sulfide group being particularly preferred. Among these, those containing 70 mol% or more, preferably 80 mol% or more, of the p-phenylene sulfide group are suitable from the point of view of physical properties such as heat resistance, formability, and mechanical properties.Among these PAS resins, a high-molecular-weight polymer with a substantially straight-chain structure, obtained by condensation polymerization from a monomer consisting mainly of a bifunctional halogen-aromatic compound, is particularly preferred. It should be noted that the PAS resin used in the present embodiment can be a mixture of two or more PAS resins with different molecular weights.

[0018] Note that in addition to the PAS resin with a straight-chain structure, an example is a polymer in which a branched or cross-linked structure is formed partially by using a small amount of a monomer, such as a polyhalogenated aromatic compound with three or more halogen substituents, during condensation polymerization.

[0019] Another example is a polymer in which a straight-chain structural polymer with low molecular weight is heated to a high temperature in the presence of oxygen or similar to increase the melt viscosity through oxidative cross-linking or thermal cross-linking in order to improve formability.

[0020] In the present embodiment, the viscosity of the resin composition tends to increase due to the high content of fibrous and non-fibrous inorganic fillers, and it is preferable to use a PAS resin with a low molecular weight. A lower molecular weight results in a higher degree of crystallinity, leading to reduced water absorption. Consequently, this helps maintain dimensional stability in high-humidity environments. Conversely, if the molecular weight of the PAS resin is too low, the toughness tends to decrease, which can be particularly detrimental when using the resin composition for the lens tube, with regard to cracking during lens insertion and creep deformation during use. Therefore, the viscosity at a temperature of 310 °C and a shear rate of 1200 s⁻¹ is determined by the specific properties of the resin. -1measured melt viscosity of the PAS resin used as base resin in the present embodiment preferably in the range of 5 to 60 Pa·s, particularly preferably in the range of 8 to 50 Pa·s, including the case of the mixing system described above. [Fibrous inorganic filler and non-fibrous inorganic filler]

[0021] In the present embodiment, the resin composition contains a fibrous inorganic filler and a non-fibrous inorganic filler. The fibrous inorganic filler reduces shrinkage and the coefficient of linear expansion, thereby improving the mechanical properties. The non-fibrous inorganic filler reduces shrinkage rate and shrinkage rate anisotropy. Water absorption is reduced by including relatively large amounts of both the fibrous and non-fibrous inorganic fillers.

[0022] In the present embodiment, the resin composition contains 80 to 300 parts by mass of the fibrous inorganic filler and the non-fibrous inorganic filler per 100 parts by mass of the PAS resin. If the content described above is less than 80 parts by mass, the water absorption capacity may increase or the dimensional accuracy may decrease. At a content of more than 300 parts by mass, the flowability decreases, which can lead to difficulties in shaping, or the toughness decreases, which, particularly in the lens tube, can lead to cracks or similar defects during the press fit of the lens during manufacturing. The content is preferably 88 to 250 parts by mass, more preferably 90 to 230 parts by mass, and even more preferably 100 to 210 parts by mass.

[0023] The fibrous inorganic filler and the non-fibrous inorganic filler are described below. (Fiber-like inorganic filler)

[0024] For fibrous inorganic fillers, "fibrous" means a shape with a varying diameter ratio of 1 to 4 and an average fiber length (cut length) of 0.01 to 3 mm in the initial shape (mold before melt forming). The ratio of the different diameters is "main diameter of a section perpendicular to a longitudinal direction (longest linear distance of the section) / small diameter of the section (longest linear distance perpendicular to the main diameter)" and can be calculated using a scanning electron microscope and image processing software. A manufacturer's value (a value published by a manufacturer in a catalog, etc.) can be used for the average fiber length (cut length).

[0025] Examples of fibrous inorganic fillers include, in particular, mineral fibers such as glass fibers, carbon fibers, zinc oxide fibers, titanium oxide fibers, wollastonite, silicon dioxide fibers, silicon dioxide-aluminum oxide fibers, zirconium dioxide fibers, boron nitride fibers, silicon nitride fibers, boron nitride fibers, and potassium titanium dioxide fibers, and metal fiber materials such as stainless steel fibers, aluminum fibers, titanium fibers, copper fibers, and brass fibers, with one or more types of these being suitable. Among these, glass fibers and carbon fibers are preferred.

[0026] Examples of glass fibers brought to market include a cut glass fiber (ECS03T-790DE, average fiber diameter: 6 µm) manufactured by Nippon Electric Glass Co., Ltd., a cut glass fiber (CS03DE 416A, average fiber diameter: 6 µm) manufactured by OWENS CORNING JAPAN LLC, a cut glass fiber (ECS03T-747H, average fiber diameter: 10.5 µm) manufactured by Nippon Electric Glass Co., a cut glass fiber (ECS03T-747, average fiber diameter: 13 µm) manufactured by Nippon Electric Glass Co., and a cut strand with irregular cross-sections CSG 3PA-830 (major diameter 28 µm, minor diameter 7 µm) manufactured by Nitto Boseki Co., Ltd. and a cut strand with irregular cross-sections CSG 3PL-962 (main diameter 20 µm, secondary diameter 10 µm), manufactured by Nitto Boseki Co., Ltd.

[0027] The fibrous inorganic filler can be treated with various surface treatment agents, such as epoxy-based compounds, isocyanate-based compounds, silane-based compounds, titanate-based compounds, and fatty acids, which are commonly known. Surface treatment improves adhesion with the PAS resin. The surface treatment agent can be applied to the fibrous inorganic filler prior to material production and subjected to surface or convergence treatment, or it can be added concurrently during material production.

[0028] The fiber diameter of the fibrous inorganic filler is not limited, but can be, for example, 5 µm or more and 30 µm or less in the initial form (mold before kneading the melt). Here, the fiber diameter of the inorganic fiber filler refers to the main diameter of the fiber segment of the inorganic fiber filler. (Non-fibrous inorganic filler)

[0029] Examples of non-fibrous inorganic fillers include granular powder and platelet-shaped inorganic fillers. For an inorganic filler in the form of a granular powder, "granular powder" means a shape (including spherical shapes) with a diameter ratio of 1 to 4 and an aspect ratio of 1 to 2. For a platelet-shaped inorganic filler, "platelet-shaped" means a shape with a diameter ratio greater than 4 and an aspect ratio of 1 to 500.

[0030] Both shapes are initial shapes (molds before melting). Note that the elongation ratio is "longest linear distance in a longitudinal direction / small diameter of a cross-section perpendicular to the longitudinal direction (the longest linear distance perpendicular to a line of the longest distance in the cross-section)".

[0031] Examples of inorganic fillers in granular form include carbon black, silica, quartz powder, glass beads, glass powder, talc (granules), silicates such as calcium silicate, aluminum silicate, and diatomaceous earth, metal oxides such as iron oxide, titanium oxide, zinc oxide, and granular aluminum oxide, metal carbonates such as calcium carbonate and magnesium carbonate, metal sulfates such as calcium sulfate and barium sulfate, silicon carbide, silicon nitride, boron nitride, and various metal powders, and one or more of these types may be used. Among these, calcium carbonate, talc, and glass beads are preferable.

[0032] Examples of calcium carbonate placed on the market include Whiton P-30 (average particle size (50%d): 5 µm), manufactured by Toyo Fine Chemical Co., Ltd. Examples of talc placed on the market include LMS100, LMR100, PKP80 and PKP53S, manufactured by FUJI TALC INDUSTRIAL CO.LTD. Examples of glass beads placed on the market include EGB731A (average particle size (50%d): 20 µm), manufactured by Potters-Ballotini Co., Ltd. and EMB-10 (average particle size (50%d): 5 µm), manufactured by Potters-Ballotini Co., Ltd.

[0033] The granular, powdered inorganic filler can also be surface-treated in the same way as the fibrous inorganic filler.

[0034] Examples of platelet-shaped inorganic fillers include glass flakes, talc (platelet-shaped), mica, kaolin, clay, aluminum oxide (platelet-shaped), and various types of metal foil, with one or more of these types being used. Among these, glass flakes and talc are preferred.

[0035] Examples of glass flakes brought to market include REFG-108 (average particle size (50%d): 623 µm), manufactured by Nippon Sheet Glass Co., Ltd; fine flakes (average particle size (50%d): 169 µm), manufactured by Nippon Sheet Glass Co., Ltd; REFG-301 (average particle size (50%d): 155 µm), manufactured by Nippon Sheet Glass Co., Ltd; and REFG-401 (average particle size (50%d): 310 µm), manufactured by Nippon Sheet Glass Co., Ltd.

[0036] Examples of talc products marketed include Crown Talk PP, manufactured by Matsumura Sangyo Co., Ltd., and Talcan Powder PKNN, manufactured by HAYSHI KASEI CO., LTD.

[0037] The platelet-shaped inorganic filler can also be surface-treated in the same way as the fibrous inorganic filler.

[0038] In the present embodiment, the mass ratio of the fibrous inorganic filler to the non-fibrous inorganic filler is preferably 0.2 to 4.5, more preferably 0.25 to 2.5, and even more preferably 0.5 to 2.3, with regard to dimensional accuracy and mechanical strength. To improve dimensional accuracy, it is advantageous to use less fibrous inorganic filler than non-fibrous inorganic filler. Thus, the mass ratio described above is preferably 0.2 to 2.5, more preferably 0.2 to 2.3, in the case of a lens tube, and preferably 0.5 to 3.5 in the case of a housing. Particularly in the lens tube, increasing the ratio of the non-fibrous inorganic filler as described above prevents the stiffness from becoming too high, which is preferable from the point of view that cracks during the pressing of the lens should be easily prevented. [Elastomer]

[0039] In the present embodiment, the elastomer content in the resin composition is 10% by mass or less. Since the presence of the elastomer increases water absorption or generates gas, the elastomer should either be absent entirely or, if present, only in an extremely small quantity. The presence of the elastomer is particularly important in the case of the lens tube, as the gas can cause the lens to fog. Therefore, in the present embodiment, the elastomer content in the resin composition is 10% by mass or less. If the content described above exceeds 10% by mass, gas formation will lead to lens fogging.The elastomer content is preferably 7.5% by mass or less, more preferably 6.5% by mass or less, even more preferably 5% by mass or less, particularly preferably 3% by mass or less, most preferably 2.5% by mass or less, ideally 0% by mass. It should be noted that adding the elastomer to the resin composition used for the lens tube is desirable to increase toughness in order to prevent cracking due to lens insertion. However, increasing the elastomer content has the disadvantage of causing lens fogging due to gas formation.To use a resin composition that does not contain an elastomer to prevent gas formation, the ratio between the fibrous inorganic filler and the non-fibrous inorganic filler can be adjusted, or the viscosity of the PAS resin can be adjusted as described above to prevent cracking due to interference fit.

[0040] The elastomer is not limited. Examples of elastomers include those containing a structural unit derived from an α-olefin and a structural unit derived from an α,β-unsaturated acid glycidyl ester as copolymerization components, and may also contain a structural unit derived from a (meth)acrylic acid ester. The elastomer can be used alone or in combination with two or more types.

[0041] Specific examples of the elastomer include a glycidyl methacrylate-grafted, modified ethylene copolymer, an ethylene-glycidyl methacrylate copolymer, an ethylene-glycidyl methacrylate-methyl acrylate copolymer, an ethylene-glycidyl methacrylate-ethyl acrylate copolymer, an ethylene-glycidyl methacrylate-propyl acrylate copolymer, and an ethylene-glycidyl methacrylate-butyl acrylate copolymer. Among these, the ethylene-glycidyl methacrylate copolymer and the ethylene-glycidyl methacrylate-methyl acrylate copolymer are preferred. Specific examples of the ethylene-glycidyl methacrylate copolymer and the ethylene-glycidyl methacrylate-methyl acrylate copolymer include "Bond First" (manufactured by SUMITOMO CHEMICAL COMPANY, LIMITED). [Alkoxysilane compound]

[0042] In the present embodiment, an alkoxysilane compound may be included to prevent burr formation. The alkoxysilane compound is not limited, and examples include an alkoxysilane such as an epoxyalkoxysilane, an aminoalkoxysilane, a vinylalkoxysilane, and a mercaptoalkoxysilane, and one or more of these may be used. It should be noted that the number of carbon atoms in the alkoxy group is preferably 1 to 10, and particularly preferably 1 to 4.

[0043] Examples of epoxyalkoxysilanes are a γ-glycidoxypropyltrimethoxysilane, a β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane and a γ-glycidoxypropyltriethoxysilane.

[0044] Examples of aminoalkoxysilane include γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropylmethyldimethoxysilane, γ-aminopropylmethyldiethoxysilane, N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-diallylaminopropyltrimethoxysilane and γ-diallylaminopropyltriethoxysilane.

[0045] Examples of vinylalkoxysilane are vinyltrimethoxysilane, vinyltriethoxysilane and vinyltris(β-methoxyethoxy)silane.

[0046] Examples of mercaptoalkoxysilane are γ-mercaptopropyl nmethoxysilane and γ-mercaptopropyl nethoxysilane.

[0047] Among these, epoxyalkoxysilane and aminoalkoxysilane are preferred, and γ-aminopropyltriethoxysilane is particularly preferred.

[0048] In the present embodiment, the addition of the alkoxysilane compound is not strictly necessary, but 0 to 5 parts by mass of it per 100 parts by mass of the PAS resin may be added to prevent burr formation. [Other ingredients]

[0049] In the resin composition according to the present embodiment, in addition to the above components, a known additive, which is generally added to a thermoplastic resin and a thermosetting resin, i.e., a thermoplastic resin other than the PAS resin, a burr inhibitor other than the alkoxysilane compound, a mold release agent, a lubricant, a plasticizer, a flame retardant, a colorant, such as a dye and a pigment, a crystallization accelerator, a crystal nucleation agent, various antioxidants, a thermal stabilizer, a weathering stabilizer, a corrosion inhibitor, and the like, can be mixed to impart the desired properties according to the purpose to such an extent that the effect of the resin composition is not impaired.However, if an amorphous thermoplastic resin other than PAS resin is used as the thermoplastic resin, the absolute value of the shrinkage rate is advantageously reduced, but the water absorption rate tends to be high. Therefore, the addition of the amorphous thermoplastic resin is limited to a small amount, preferably 10% by weight or less, and more preferably 5% by weight or less of the total resin composition.

[0050] The housing part for the vehicle camera according to the present embodiment is formed by injection molding using the resin composition described above, according to a predetermined procedure.

[0051] As described above, the housing part for the vehicle camera according to the present embodiment satisfies condition (A) that an absolute value of (shrinkage rate in a direction perpendicular to a flow direction) - (shrinkage rate in the flow direction) is 0.5% or less when the resin composition according to the present embodiment is used and injection molded under predetermined conditions. To satisfy condition (A), the anisotropy of the shrinkage rate can be reduced by increasing the ratio of the non-fibrous inorganic filler with a small aspect ratio, or the absolute value of the shrinkage rate can be reduced by increasing the content of the fibrous filler and / or the non-fibrous inorganic filler.

[0052] Note that the absolute value of the shrinkage rate in a direction perpendicular to the flow direction is preferably 0.65 or less.

[0053] Similarly, the housing part for the vehicle camera according to the present embodiment satisfies condition (B) that the water absorption rate of a molded product of a predetermined size, injection molded under a predetermined condition using the resin composition according to the present embodiment, is 0.3% or less when subjected to a hot water immersion test at 80°C for 300 hours. To satisfy condition (B), adjustments can be made by reducing the elastomer content or by adding a filler that can increase the water absorption rate, such as a porous inorganic filler.

[0054] In the housing part for the vehicle camera according to the present embodiment, the average value of a linear expansion coefficient in one flow direction and a linear expansion coefficient in a direction perpendicular to the flow direction at 150 °C is preferably 35 (× 10 -6 K -1 ) or less. The average value of the linear expansion coefficients within the range described above allows for a reduction in deformation due to temperature changes. Preferably, the average value of the linear expansion coefficients is between 2 and 30 (× 10 -6 K -1 It should be noted that the linear expansion coefficients are adjustable depending on the content of the fibrous inorganic filler or the non-fibrous inorganic filler.

[0055] Preferably, the housing component for the vehicle camera according to the present embodiment exhibits a creep deformation of 3 mm or less when a stress of 67 MPa is applied for 500 hours at a temperature of 120 °C. The creep deformation within the range described above makes it particularly possible to reduce deformation before and after pressing in the lens in the case of the lens tube. It should be noted that the amount of creep deformation is adjustable depending on the molecular weight of the PAS resin, the content of the fibrous inorganic filler, the content of the non-fibrous inorganic filler, the content of the elastomer, or similar components.

[0056] When the housing part for the vehicle camera is attached to the lens tube according to the present embodiment, a high degree of roundness is desired. The present embodiment offers superior dimensional accuracy under high temperatures and high humidity, as described above, and thus provides a high degree of roundness in the same environment. EXAMPLES

[0057] Although the present embodiment is described in more detail by means of examples, the present embodiment is not limited to the following examples. [Examples 1 to 4 and comparison examples 1 to 4]

[0058] In all examples and comparative examples, the raw material components listed in Table 1 were dry-mixed, then fed into a twin-screw extruder at a cylinder temperature of 320 °C (the fibrous inorganic filler and the non-fibrous inorganic filler were added separately via a side feed section of the extruder), melt-kneaded, and pelletized. Please note that in Table 1, the numerical value of each component indicates its mass fraction. Details of the raw material components used are described below. (1) PAS resin - PPS1: Polyphenylene sulfide resin (melt viscosity: 50 Pa·s (shear rate: 1200 s) -1 , 310 °C)), manufactured by POLYPLASTICS CO., LTD. - PPS2: Polyphenylene sulfide resin (melt viscosity: 30 Pa·s (shear rate: 1200 s) -1 , 310 °C)), manufactured by POLYPLASTICS CO., LTD. - PPS3: Polyphenylene sulfide resin (melt viscosity: 80 Pa·s (shear rate: 1200 s) -1 , 310 °C)), manufactured by POLYPLASTICS CO., LTD. (Measurement of the melt viscosity of PPS resins)

[0059] The melt viscosity of the PPS resins described above was measured as follows.

[0060] The melt viscosity was determined using a capilograph from Toyo Seiki Seisaku-sho, Co., Ltd. at a cylinder temperature of 310 °C and a shear rate of 1200 s⁻¹. -1 measured using a flat plunger of 1 mmφ × 20 mmL as a capillary according to ISO11443. (2) Fibrous inorganic filler - Fiber optic: cut strand ECS03T-717, diameter: 13 mm, average fiber length: 3 mm, manufactured by Nippon Electric Glass Co, Ltd. (3) Non-fibrous inorganic filler - Calcium carbonate: Whiton P-30, manufactured by Toyo Fine Chemical Kaisha, Co., Ltd. - Glass beads: EGB731A manufactured by Potters-Ballotini Co, Ltd. - Glass flakes: REFG-108 manufactured by Nippon Sheet Glass Co, Ltd. - Talc: Crown Talk PP manufactured by Matsumura Sangyo Co., Ltd. (4) Elastomer - Olefin copolymer: Modiper (registered trademark) A4300 (a copolymer obtained by grafting 70 parts by mass of an ethylene glycidyl methacrylate copolymer with 30 parts by mass of a methyl methacrylate butyl acrylate copolymer), manufactured by NOF CORPORATION. (5) Alkoxysilane compound

[0061] Silane compound: γ-Aminopropyltriethoxysilane KE-903P, manufactured by Shin-Etsu Chemical Co, Ltd. [Rating](1) Shrinkage rate

[0062] Using granules produced in the examples and comparison examples, a test piece measuring 80 mm × 80 mm × 1 mm with a 2 mm × 1 mm lateral gate in the center of one side was injection molded under conditions of a cylinder temperature of 320 °C, a mold temperature of 140 °C, and a holding pressure of 70 MPa. A three-dimensional measuring device (CRYSTA-Apec C574 three-dimensional dimensional measuring device, manufactured by Mitsutoyo Co., Ltd.) was used to measure the size at a position 20 mm from the end of the molded product in a perpendicular direction (flow direction) orthogonal to the gate side and the anti-gate side of the molded test piece. A value resulting from the difference between the mold size at this position and the mold size was determined as the flow-direction shrinkage rate (X).Similarly, for a direction (perpendicular to the flow direction), the size was measured at a position 20 mm from the end on the gate side, and a value obtained by dividing the difference between a mold size at this position and the mold size was determined as the shrinkage rate in a direction (Y) perpendicular to the flow direction. Note that the shrinkage rate in each direction was calculated as the average of samples with n = 5. The anisotropy of the shrinkage rate was calculated as the shrinkage rate in the direction (Y) perpendicular to the flow direction minus the shrinkage rate in the flow direction (X). The measurement and calculation results are presented in Table 1. (2) Water absorption rate

[0063] Using granules produced in the examples and comparison examples, a test piece measuring 80 mm × 80 mm × 2 mm was injection molded under conditions of a cylinder temperature of 320 °C, a mold temperature of 140 °C, and a holding pressure of 70 MPa. The molded test piece was subjected to a hot water immersion test at 80 °C for 300 hours. The mass before and after immersion was measured, and a value was determined by dividing the difference obtained by subtracting the mass before immersion from the mass after immersion by the mass before immersion. The value exceeding 0.3% was rated as C, the value exceeding 0.3% or less and 0.2% was rated as B, and the value 0.2% or less was rated as A. The evaluation results are presented in Table 1. (3) Melt viscosity of the resin composition

[0064] Using a pellet produced in each of the examples and comparison examples, the melt viscosity was determined at a cylinder temperature of 310 °C and a shear rate of 1000 s⁻¹. -1 measured using a flat stamp of 1 mmφ × 20 mmL as a capillary according to ISO 11443 with a capilograph from Toyo Seiki Seisaku-sho, Co., Ltd. (4) Linear expansion coefficient

[0065] Using granules prepared in the examples and comparative examples, a test specimen was in Fig.(Tensile test specimen type 1A according to ISO 527-1, 2 according to ISO 3167) was injection molded under conditions of a cylinder temperature of 320 °C, a mold temperature of 140 °C, and a holding pressure of 70 MPa. Two hatched sections of the test specimen were each cut out in a prismatic shape of 5 mm × 4 mm × 10 mm to obtain one test specimen FD for evaluation, whose longitudinal direction was the flow direction, and one test specimen TD for evaluation, whose longitudinal direction was perpendicular to the flow direction. After annealing test specimens FD and TD for 1 hour at 250 °C, the coefficients of linear expansion were measured using a Rigaku Corporation TMA8310 linear expansion gauge at a measurement temperature of -40 to 240 °C, a temperature rise rate of 2 °C / min, and a load of 4.0 kPa. Subsequently, the linear expansion coefficient in each direction at 150 °C was determined from the result and the average value was calculated.

[0066] The average value, which is 30 (× 10 -6 K -1 A score of 30 or less was rated A, an average score exceeding 30 but 35 or less was rated B, and an average score exceeding 35 was rated C. The rating results are shown in Table 1.

[0067] Note that the unit of the numerical value representing the length in Fig. indicates "mm". (5) Creep deformation

[0068] The extent of deformation after 500 hours was measured using the NO. 145 creep tester, manufactured by YASUDA SEIKI SEISAKUSHO, LTD., at an ambient temperature of 120 °C and a loading stress of 67 MPa. Deformations of 2.5 mm or less were rated A, those greater than 2.5 mm and 3 mm or less were rated B, and those greater than 3 mm were rated C. The evaluation results are listed in Table 1. (6) Press-fit properties

[0069] Using granules produced in the examples and comparative examples, a molded part was produced with the properties shown in Fig. The mold shown in section 2 was injection molded under conditions of a cylinder temperature of 320 °C, a mold temperature of 140 °C, and a holding pressure of 70 MPa. The mold is shown in section 2. Fig.The molded part shown has a shape in which a cylinder with a conical through-hole in the center of the upper surface of a base with a regular hexagonal column shape is positioned. The through-hole also penetrates the base and is shaped to have a smaller diameter from the top to the bottom. That is, the diameter of the through-hole is 3.6 mm at the top and 3.472 mm at the bottom. A pin (made of SUS304, modulus of elasticity: 190 Pa) with a diameter of 3.61 mm and a length of 20 mm was then inserted through the hole at the top of the cylindrical part at a speed of 1 mm / min, and the appearance of cracks was visually observed. This was evaluated in each of the examples and comparison examples of molded products with n = 3, where no cracks were rated A, 1 to 2 cracks were rated B, and all 3 cracks were rated C. The evaluation results are shown in Table 1.

[0070] The unit of the numerical value that represents the length in Fig. The unit of measurement is "mm". (7) Gas

[0071] Using granules produced in the examples and comparative examples, a test specimen measuring 80 mm × 80 mm × 2 mm was injection molded under conditions of a cylinder temperature of 320 °C, a mold temperature of 140 °C, and a holding pressure of 70 MPa. The molded specimen was then finely ground into a square of approximately 1 to 2 mm and a fogging test was performed. Specifically, 20 g of the ground pieces were pre-dried for 3 hours at 140 °C, placed in a test tube, a Petri dish was positioned over the opening of the test tube, and the sample was heated in a block bath at 180 °C for 8 hours. After cooling, the fogging of the Petri dish was visually observed. A case with no fogging was rated A, a case with slight fogging B, and a case with clearly visible fogging C. The evaluation results are listed in Table 1. [Table 1] Examples Comparative examples 1 2 3 4 1 2 3 4 PAS resin PPS1 (MV=50Pa·s) 100 100 100 PPS2 (MV=30Pa·s) 100 100 100 100 PPS3 (MV=80Pa·s) 100 Fibrous inorganic filler fiber optics 99,1 50,9 81,6 102,8 101,8 36,6 60,1 102,8 Non-fibrous inorganic filler calcium carbonate 99,1 - 35,0 51,4 - 36,6 - 51,4 glass beads - 101,8 - - 11,5 - - - Glass flakes - - - - - - 60,1 - talc - - - - 10,2 - - - Fibrous inorganic filler + non-fibrous inorganic filler 198,2 152,7 116,6 154,2 123,4 73,3 120,2 154,2 Fibrous inorganic filler / non-fibrous inorganic filler 1,0 0,5 2,3 2,0 4,7 1,0 1,0 2,0 Elastomer EGMA 0 0 14,0 0 0 0 25,2 0 Elastomer (mass% conversion) 0 0 6,1 0 0 0 13,6 0 alkoxysilane compound 0 0 0 0,5 0 0 0 0,5 shrinkage rate Flow direction (X) 0,26 0,24 0,14 0,15 0,22 0,28 0,13 0,20 Direction perpendicular to the flow direction (Y) 0,63 0,59 0,60 0,60 0,75 0,79 0,39 0,74 YX 0,37 0,35 0,46 0,45 0,53 0,51 0,26 0,54 Water intake rate A A B A A A C A melt viscosity 343 232 251 304 180 311 283 412 Linear expansion coefficient (x 10 -6 K -1 ) A A B A B B B A Creep deformation A A B B B A B A Press-fit properties B A A B C A A A gas A A B A A A C A

[0072] Table 1 shows that in examples 1 to 4, good results were achieved in all evaluation categories, while in comparison examples 1 to 4, good results were not achieved in all evaluation categories at the same time. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] DE 416 A

[0026]

Claims

[1] A housing part for a vehicle camera, obtained by injection molding a resin composition comprising 100 to 300 parts by mass of a fibrous inorganic filler and a non-fibrous inorganic filler to 100 parts by mass of a polyarylene sulfide resin and having an elastomer content of 10 percent by mass or less, and that meets the following conditions (A) and (B): (A) when a molded part measuring 80 mm × 80 mm × 1 mm is injection molded using the resin composition under conditions of a cylinder temperature of 320 °C, a mold temperature of 120 °C and a holding pressure of 70 MPa, an absolute value of (shrinkage rate in one direction perpendicular to a flow direction) - (shrinkage rate in the flow direction) is 0.5% or less; and (B) the water absorption rate of a molded part measuring 80 mm × 80 mm × 2 mm, injection molded using the resin composition under conditions of a cylinder temperature of 320 °C, a mold temperature of 120 °C and a holding pressure of 70 MPa, is 0.3% or less when subjected to a hot water immersion test at 80 °C for 300 hours. [2] Housing part for the vehicle camera according to claim 1, wherein the polyarylene sulfide resin has a melt viscosity of 70 Pa·s or less, measured at a temperature of 310 °C and a shear rate of 1200 s -1 . [3] Housing part for the vehicle camera according to claim 1 or 2, wherein the mass ratio of the fibrous inorganic filler to the non-fibrous inorganic filler is 0.2 to 4.

5. [4] Housing part for the vehicle camera according to one of claims 1 to 3, wherein an average value of a linear expansion coefficient in a flow direction and a linear expansion coefficient in a direction perpendicular to the flow direction at 150 °C 35 (× 10 -6 K -1 ) or less. [5] The housing part for the vehicle camera according to any one of claims 1 to 4, wherein the amount of creep deformation when a voltage of 67 MPa is applied for 500 hours at a temperature of 120 °C is 3 mm or less. [6] A housing part for a vehicle camera, wherein the housing part is used in a vehicle camera which is mounted in a front grille of a vehicle or at a position facing a windscreen. [7] The housing part for the vehicle camera according to any one of claims 1 to 6, wherein the housing part is a lens tube to support and hold a lens in the vehicle camera in a press fit condition. [8] Housing part for the vehicle camera according to any one of claims 1 to 6, wherein the housing part is a housing that forms an outer surface of the vehicle camera.