Thermoplastic resin composition, molded article and vehicle window glass

Abstract

The present invention provides a thermoplastic resin composition which is obtained by blending (A) a thermoplastic resin, (B) a hydroxyl group-containing (meth)acrylic resin and (C) an inorganic filler, and which is used for a component to be bonded to a vehicle window glass with a urethane-based adhesive. By using this thermoplastic resin composition, it is possible to obtain a molded article which achieves a balance between mechanical characteristics required in electrical / electronic equipment components, vehicle components, mechanical components, etc., and adhesive properties with a urethane-based adhesive used when bonding to a vehicle window glass.

Description

Thermoplastic resin composition, molded article, and vehicle window glass

[0001] The present invention relates to a thermoplastic resin composition having dramatically improved adhesive properties with urethane adhesives, suitable for use in resin parts such as glass holders to be attached to vehicle window glass and camera brackets.

[0002] Thermoplastic resins are widely used industrially because they are easy to process and many of them have excellent mechanical properties, heat resistance, and other characteristics.

[0003] Among these, polybutylene terephthalate resin (hereinafter sometimes abbreviated as PBT resin) is particularly excellent in heat resistance, chemical resistance, electrical properties, dimensional stability, etc., and is therefore widely used as a material for various electrical and electronic equipment components, vehicle components for automobiles, trains, electric trains, etc., and for manufacturing other general industrial products.

[0004] In recent years, with the advancement of information and communication technology in the automotive industry, automobiles equipped with systems (advanced driver assistance systems) that utilize advanced information technology to assist drivers in safe driving have become increasingly common. Such automobiles are equipped with numerous sensors and cameras, as well as associated electrical components, that accurately and quickly collect and transmit information about the vehicle's surroundings. Polybutylene terephthalate resin, which has excellent properties as an engineering plastic, is often used as a case or cover material for these components.

[0005] On the other hand, in such applications, electrical components such as sensors and cameras must be fixed somewhere on the vehicle body, and in order to acquire high-speed radio waves and peripheral information, they may be attached directly to the surface of glass such as the windshield. A common method for fixing plastic electrical components to the glass surface is to use a bonding method that uses an adhesive, and urethane adhesives are often selected for their adhesiveness to glass.

[0006] On the other hand, urethane adhesives are mainly used with consideration given to bonding with glass, and in many cases, sufficient consideration is not given to adhesion with the other bonding partner, the plastic, which can result in poor adhesion between the plastic and the urethane adhesive.

[0007] As a conventional method for improving the adhesion problems between plastics and adhesives, a method of applying a primer (undercoat) to the surface of plastics that is difficult to bond, as disclosed in Patent Document 1, has been proposed.

[0008] Also, Patent Document 2 discloses a method of improving the adhesiveness with a urethane adhesive by incorporating polycarbonate resin, glass fiber, and a phosphorus-based stabilizer into polybutylene terephthalate resin.

[0009] JP 2019-84520 A JP 2021-25032 A

[0010] However, the method using the primer described in Patent Document 1 requires a primer application step and a drying step, which increases production costs. Furthermore, because the primer contains a certain amount of solvent, the odor of the vaporized gas deteriorates the working environment, which reduces workability.

[0011] Furthermore, although the technology described in Patent Document 2 shows a certain improvement in the adhesiveness of polybutylene terephthalate resin with a urethane adhesive, it does not satisfy the adhesiveness required for resin parts to be assembled to automobile window glass.

[0012] Therefore, an object of the present invention is to solve the above-mentioned problems and to provide a thermoplastic resin composition that has dramatically improved adhesion to a urethane-based adhesive when bonded to a window glass for a vehicle such as an automobile with a urethane-based adhesive, without requiring a pre-process such as primer application; a molded article made from the thermoplastic resin composition; and a vehicle window glass to which the molded article is bonded with a urethane-based adhesive.

[0013] As a result of extensive research into solving the above-mentioned problems, the present inventors have found that the above-mentioned problems can be solved by blending (A) a thermoplastic resin, (B) a hydroxyl group-containing (meth)acrylic resin, and (C) an inorganic filler, and have arrived at the present invention.

[0014] That is, the present invention has the following features. (1) A thermoplastic resin composition for a component to be bonded to a vehicle window glass with a urethane-based adhesive, the component comprising: (A) 100 parts by weight of a thermoplastic resin; (B) 0.1 to 30 parts by weight of a hydroxyl group-containing (meth)acrylic resin; and (C) 15 to 100 parts by weight of an inorganic filler. (2) The thermoplastic resin composition according to (1), wherein the thermoplastic resin (A) comprises a polybutylene terephthalate resin. (3) The thermoplastic resin composition according to (1) or (2), wherein the hydroxyl group value of the hydroxyl group-containing (meth)acrylic resin (B) is 30 to 500 mgKOH / g. (4) The thermoplastic resin composition according to any one of (1) to (3), wherein the inorganic filler (C) comprises glass fiber. (5) A molded product to be bonded to a vehicle window glass with a urethane-based adhesive, the molded product being obtained by molding the thermoplastic resin composition according to any one of (1) to (4). (6) The molded article according to (5), which is directly bonded with a urethane adhesive. (7) A window glass for a vehicle to which the molded article according to (5) is bonded with a urethane adhesive.

[0015] According to the thermoplastic resin composition of the present invention, it is possible to obtain a molded article that satisfies both the mechanical properties required for electrical and electronic equipment parts, vehicle parts, machine parts, etc., and the adhesiveness with a urethane-based adhesive used for bonding to a vehicle window glass (hereinafter referred to as urethane adhesiveness).

[0016] The present invention will be described in detail below with reference to embodiments.

[0017] (A) Thermoplastic Resin The thermoplastic resin (A) constituting the present invention may be any melt-moldable resin. Examples thereof include polyethylene resin, polypropylene resin, polyamide resin, polyester resin, polycarbonate resin, polyacetal resin, polyphenylene oxide resin, polyphenylene sulfide resin, polysulfone resin, polyimide resin, AS resin (acrylonitrile / styrene copolymer), hydrogenated or unhydrogenated SBS resin (styrene / butadiene / styrene triblock copolymer), hydrogenated or unhydrogenated SIS resin (styrene / isoprene / styrene triblock copolymer), polymethylpentene resin, cyclic olefin resin, and cellulose resin such as cellulose acetate. These thermoplastic resins may be used alone or in combination of two or more. Among these, polyester resins are preferred, and polybutylene terephthalate resin is more preferred.

[0018] (Polybutylene Terephthalate Resin) Polybutylene terephthalate resin is a polymer obtained by a conventional polymerization method, such as polycondensation, using terephthalic acid or its ester-forming derivative and 1,4-butanediol or its ester-forming derivative as the main components. It may contain other copolymerization components, for example, in an amount of about 20 parts by weight or less per 100 parts by weight of polybutylene terephthalate resin, as long as its properties are not impaired. Preferred examples of these polymers and copolymers include polybutylene terephthalate, polybutylene (terephthalate / isophthalate), polybutylene (terephthalate / adipate), polybutylene (terephthalate / sebacate), polybutylene (terephthalate / decanedicarboxylate), polybutylene (terephthalate / naphthalate), and poly(butylene / ethylene) terephthalate, which may be used alone or in combination of two or more.

[0019] The method for producing the polybutylene terephthalate resin used in this example of the present invention is not particularly limited, and known polycondensation methods, ring-opening polymerization methods, etc. can be used. Either batch polymerization or continuous polymerization can be used, and any of a method involving transesterification and polycondensation, and a method involving direct polymerization polycondensation (direct polymerization) can be applied. Continuous polymerization is preferred because it can reduce the amount of carboxyl end groups and has a greater effect of improving fluidity, while direct polymerization is preferred from the standpoint of cost.

[0020] In order to effectively promote the esterification reaction or transesterification reaction and polycondensation reaction, it is preferable to add a catalyst during these reactions. Specific examples of the catalyst include organotitanium compounds such as methyl ester, tetra-n-propyl ester, tetra-n-butyl ester, tetraisopropyl ester, tetraisobutyl ester, tetra-tert-butyl ester, cyclohexyl ester, phenyl ester, benzyl ester, tolyl ester, or mixed esters of these of titanic acid, dibutyltin oxide, methylphenyltin oxide, tetraethyltin, hexaethylditin oxide, cyclohexahexylditin oxide, didodecyltin oxide, and triethyltin hydroxide. Examples of suitable polymerization catalysts include tin compounds such as tin hydroxide, triphenyltin hydroxide, triisobutyltin acetate, dibutyltin diacetate, diphenyltin dilaurate, monobutyltin trichloride, dibutyltin dichloride, tributyltin chloride, dibutyltin sulfide, butylhydroxytin oxide, and alkylstannoic acids such as methylstannoic acid, ethylstannoic acid, and butylstannoic acid; zirconia compounds such as zirconium tetra-n-butoxide; and antimony compounds such as antimony trioxide and antimony acetate. Two or more of these catalysts can also be used in combination. From the viewpoint of the amount of carboxyl groups in the polybutylene terephthalate resin, organic titanium compounds and tin compounds are preferred, with tetra-n-butyl ester of titanic acid being even more preferred. The amount of polymerization catalyst added is preferably in the range of 0.01 to 0.2 parts by weight per 100 parts by weight of the polybutylene terephthalate resin.

[0021] The carboxyl group content of the polybutylene terephthalate resin used in one example of the present invention is preferably 20 eq / t or less, more preferably 15 eq / t or less, in order to achieve good adhesion with urethane-based adhesives. The terminal functional groups of the polybutylene terephthalate resin consist of carboxyl groups and hydroxyl groups. When the thermoplastic resin composition obtained in one example of the present invention reacts with a urethane-based adhesive, the hydroxyl groups of the polybutylene terephthalate resin and (B) hydroxyl group-containing (meth)acrylic resin react with the isocyanate groups of the urethane-based adhesive to form urethane bonds, thereby exhibiting adhesive strength. If the carboxyl group content of the (A) polybutylene terephthalate resin is high, the carboxyl groups will side-react with the isocyanate groups to form bonds other than urethane bonds, i.e., amide bonds or urea bonds, which is undesirable as it does not provide good urethane adhesive strength. The lower limit of the carboxyl group content is approximately 0 eq / t. Here, the amount of carboxyl groups in the polybutylene terephthalate resin is a value measured by dissolving the (A) polybutylene terephthalate resin in an o-cresol / chloroform solvent and then titrating the solution with ethanolic potassium hydroxide.

[0022] The polybutylene terephthalate used in one example of the present invention preferably has a melt flow rate (hereinafter sometimes abbreviated as "MFR") in the range of 5 to 80 g / 10 min under conditions of 250°C and 1000 gf. If the MFR is 5 g / 10 min or more, the flowability can be further improved. 30 g / 10 min or more is more preferable. On the other hand, if the MFR is 80 g / 10 min or less, a molded product with excellent mechanical properties can be obtained. 70 g / 10 min or less is more preferable. Note that the MFR in this specification is a value measured in accordance with ISO 1133.

[0023] Amorphous resins such as AS resin (acrylonitrile / styrene copolymer) and polycarbonate resin can be easily melt-kneaded with polybutylene terephthalate resin, and by blending these resins in combination with polybutylene terephthalate resin, molded articles with excellent dimensional stability can be produced. Polycarbonate resin is particularly preferred from the viewpoint of adhesion to urethane adhesives.

[0024] Polycarbonate resins are polymers obtained by reacting raw materials mainly composed of dihydric phenols and carbonate precursors such as phosgene or carbonate ester compounds, etc. For example, they are produced by reacting dihydric phenols with carbonate precursors such as phosgene or by transesterification of dihydric phenols with carbonate precursors such as diphenyl carbonate in a solvent such as methylene chloride.

[0025] The melt viscosity of the polycarbonate resin may be appropriately selected and determined, but the melt volume rate (hereinafter sometimes abbreviated as MVR) measured at 300°C and 1.2 kgf is preferably 5.0 to 30.0 cm ３ / 10 minutes range is preferred. ３ On the other hand, when the melt viscosity is 5.0 cm / 10 minutes or less, the mechanical properties are further improved. ３ If the time is 10 minutes or more, the fluidity is further improved. ３ / 10 minutes. Two or more polycarbonate resins with different viscosities may be mixed, and polycarbonate resins with melt viscosities outside the above range may also be mixed. Polycarbonate resins with such melt viscosities are available, for example, from Mitsubishi Engineering-Plastics Corporation under the trade name "Iupilon" (registered trademark).

[0026] When such an amorphous resin is blended, in order to maintain the function of the (A) thermoplastic resin, the preferred ratio of polybutylene terephthalate resin:amorphous resin is 100:0 to 50:50 (weight ratio) when the total amount of the polybutylene terephthalate resin and the amorphous resin is taken as 100 parts by weight.

[0027] In order to ensure dimensional stability, when an amorphous resin is blended, the ratio of polybutylene terephthalate resin to amorphous resin is preferably 90:10 to 50:50 (weight ratio). By using this ratio, it is possible to achieve both adhesion to the urethane adhesive and dimensional stability.

[0028]

[0023] (B) Hydroxyl Group-Containing (Meth)acrylic Resin

[0024] The thermoplastic resin composition of the present invention is formulated with (B) a hydroxyl group-containing (meth)acrylic resin. Although a hydroxyl group-containing (meth)acrylic resin may be classified as a thermoplastic resin, it is described as component (B) to distinguish it from component (A). In other words, even if it is classified as (A) a thermoplastic resin, if it is classified as (B) a hydroxyl group-containing (meth)acrylic resin, it is treated as (B) a hydroxyl group-containing (meth)acrylic resin.

[0029] (B) The hydroxyl group-containing (meth)acrylic resin is a polymer obtained by polymerizing a (meth)acrylic monomer having a hydroxyl group, or a copolymer obtained by polymerizing a (meth)acrylic monomer having a hydroxyl group and a monomer copolymerizable with said monomer.

[0030] The (meth)acrylic monomer having a hydroxyl group is not particularly limited, but (meth)acrylic acid hydroxyalkyl esters are preferred from the viewpoint of adhesion to urethane adhesives and mechanical strength. Specific examples of (meth)acrylic acid hydroxyalkyl esters include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate.

[0031] The monomer copolymerizable with the (meth)acrylic monomer having a hydroxyl group is not particularly limited as long as it is a compound having a polymerizable unsaturated bond, and examples thereof include (meth)acrylic acid alkyl esters, (meth)acrylic acid alkoxyalkyl esters, styrene, butadiene, (meth)acrylonitrile, glycidyl (meth)acrylate, maleic anhydride, etc. From the viewpoints of adhesion to urethane adhesives and mechanical strength, (meth)acrylic acid alkyl esters and styrene are preferred.

[0032] By incorporating (B) a hydroxyl group-containing (meth)acrylic resin, the hydroxyl groups react with the isocyanate groups of the urethane adhesive to form urethane bonds, thereby exhibiting adhesive strength. Based on this mechanism, the hydroxyl value of the (B) hydroxyl group-containing (meth)acrylic resin significantly affects adhesion to urethane adhesives, and is preferably 30 mgKOH / g or more, more preferably 60 mgKOH / g or more, and most preferably 80 mgKOH / g or more. However, a higher hydroxyl value can cause an ester exchange reaction with the polybutylene terephthalate resin, resulting in a decrease in physical properties such as mechanical properties. Therefore, in consideration of the balance with adhesion to urethane adhesives, the upper limit is preferably 500 mgKOH / g or less, more preferably 300 mgKOH / g or less, and most preferably 200 mgKOH / g or less. The hydroxyl value in this specification is a value measured in accordance with JIS K 0070-1992.

[0033] The weight-average molecular weight (Mw) of the hydroxyl group-containing (meth)acrylic resin (B) is preferably 1,000 or more, more preferably 5,000 or more, and most preferably 10,000 or more. The larger the weight-average molecular weight, the smaller the amount of gas during molding, which is preferable. However, the smaller the weight-average molecular weight, the more likely the hydroxyl group-containing (meth)acrylic resin (B) is to be localized on the surface of the molded article, so the weight-average molecular weight is preferably 30,000 or less, more preferably 20,000 or less, and most preferably 15,000 or less.

[0034] The blending amount of the (B) hydroxyl group-containing (meth)acrylic resin in the present invention is in the range of 0.1 to 30 parts by weight per 100 parts by weight of the aforementioned (A) thermoplastic resin. If the blending amount of the (B) hydroxyl group-containing (meth)acrylic resin is less than 0.1 part by weight, adhesion to urethane-based adhesives will decrease. From the viewpoint of adhesion to urethane-based adhesives, the blending amount of the (B) hydroxyl group-containing (meth)acrylic resin is preferably 0.3 parts by weight or more, more preferably 0.5 parts by weight or more, and most preferably 1 part by weight or more. Furthermore, if the blending amount of the (B) hydroxyl group-containing (meth)acrylic resin exceeds 30 parts by weight, the mechanical strength of the thermoplastic resin composition will decrease. From the viewpoint of mechanical strength, the blending amount is preferably 25 parts by weight or less, more preferably 20 parts by weight or less, and most preferably 15 parts by weight or less.

[0035] (C) Inorganic Filler In the present invention, an inorganic filler (C) is blended to impart mechanical strength and other properties to the thermoplastic resin composition. From the viewpoint of dimensional stability and mechanical properties, the blending amount of the inorganic filler (C) is in the range of 15 to 100 parts by weight per 100 parts by weight of the thermoplastic resin (A). A blending amount in the range of 20 to 90 parts by weight is preferred, and a blending amount in the range of 30 to 80 parts by weight is more preferred.

[0036] In the present invention, the type of inorganic filler (C) can be any filler in the form of fiber, plate, powder, granule, etc. Specifically, examples include glass fiber, PAN (polyacrylonitrile)-based or pitch-based carbon fiber, stainless steel fiber, metal fiber such as aluminum fiber or brass fiber, organic fiber such as aromatic polyamide fiber, gypsum fiber, ceramic fiber, asbestos fiber, zirconia fiber, alumina fiber, silica fiber, titanium oxide fiber, silicon carbide fiber, rock wool, potassium titanate whisker, barium titanate whisker, aluminum borate whisker, silicon nitride whisker, and other fibrous or whisker-like fillers, and powdery, granular, or plate-like fillers such as mica, talc, kaolin, silica, calcium carbonate, glass beads, glass flakes, glass microballoons, clay, molybdenum disulfide, wollastonite, montmorillonite, titanium oxide, zinc oxide, calcium polyphosphate, graphite, barium sulfate, and other fillers, and among these, glass fiber is preferred. The type of glass fiber is not particularly limited as long as it is generally used to reinforce resins, and can be selected from, for example, long fiber type or short fiber type chopped strands, milled fibers, etc. Among these, short fiber type chopped strands are preferred, and from the viewpoint of urethane adhesiveness, chopped strands having an average fiber diameter of 13 μm or less are more preferred. Furthermore, two or more types of the above-mentioned (C) inorganic filler can also be used in combination.

[0037] The inorganic filler (C) used in the present invention may be surface-treated with a known coupling agent (e.g., a silane coupling agent such as aminosilane or epoxysilane, or a titanate coupling agent) or other surface treatment agent. The glass fibers may be coated or bundled with a thermoplastic resin such as an ethylene / vinyl acetate copolymer or a thermosetting resin such as an epoxy resin.

[0038] (Other Components) One or more additives such as a crystal nucleating agent, a mold release agent, an ultraviolet absorber, an antibacterial agent, a stabilizer, a colorant including a pigment and a dye, a lubricant, an antistatic agent, and an end-capping agent may be added to the thermoplastic resin composition of the present invention, provided that the effects of the present invention are not impaired.

[0039] In the present invention, additives such as alcohols containing hydroxyl groups may be blended to improve adhesion to urethane adhesives. Examples of alcohols include polyalkylene glycols such as polyethylene glycol and polyhydric alcohols such as pentaerythritol.

[0040] In the present invention, the nucleating agent may be either an inorganic nucleating agent or an organic nucleating agent. Examples of inorganic nucleating agents include talc, synthetic mica, clay, zeolite, magnesium oxide, calcium sulfide, boron nitride, and neodymium oxide. In order to improve dispersibility in the composition, it is preferable that the nucleating agent be modified with an organic substance. Examples of organic crystal nucleating agents include sodium benzoate, potassium benzoate, lithium benzoate, calcium benzoate, magnesium benzoate, barium benzoate, lithium terephthalate, sodium terephthalate, potassium terephthalate, sodium toluate, sodium salicylate, potassium salicylate, zinc salicylate, aluminum dibenzoate, potassium dibenzoate, lithium dibenzoate, sodium β-naphthalate, and organic carboxylic acid metal salts such as sodium cyclohexanecarboxylate, organic sulfonates such as sodium p-toluenesulfonate and sodium sulfoisophthalate, sorbitol compounds, metal salts of phenylphosphonate, and metal salts of phosphorus compounds such as sodium-2,2'-methylenebis(4,6-di-t-butylphenyl)phosphate. By incorporating these crystal nucleating agents, it is possible to obtain thermoplastic resin compositions and molded articles having excellent mechanical properties, moldability, heat resistance, and durability.

[0041] In the present invention, any of the release agents used as release agents for thermoplastic resins can be used. Specific examples include fatty acids, fatty acid metal salts, oxyfatty acids, fatty acid esters, partially saponified aliphatic esters, paraffins, low-molecular-weight polyolefins, fatty acid amides, alkylene bisfatty acid amides, aliphatic ketones, and modified silicones. Among these, fatty acid ester-based release agents are preferred from the viewpoints of urethane adhesion and suppressing a decrease in glass transparency when used in automotive applications as a composite molded article with glass.

[0042] The fatty acid ester-based release agent is composed of a tri- to hexavalent aliphatic alcohol and a fatty acid. Examples of the tri- to hexavalent aliphatic alcohol include glycerol, diglycerol, erythritol, pentaerythritol, sorbitol, triglycerol, dipentaerythritol, and tetraglycerol. These aliphatic alcohols can be used alone or in combination.

[0043] The fatty acid is preferably a linear or branched saturated fatty acid having from 5 to 30 carbon atoms, such as pentanoic acid, hexanoic acid, octanoic acid, nonanoic acid, decanoic acid, lauric acid, myristic acid, palmitic acid, stearic acid, isostearic acid, arachidic acid, behenic acid, lignoceric acid, cerotic acid, montanic acid, and melissic acid, with stearic acid being particularly preferred.

[0044] Fatty acid ester-based release agents are available, for example, from Emery Oleochemicals Japan Co., Ltd. under the trade name "Roxiol" (registered trademark), from ADEKA Corporation under the trade name "ADEKA Cizer" (registered trademark), and from Riken Vitamin Co., Ltd. under the trade name "Likestar" (registered trademark).

[0045] When a release agent is blended into the thermoplastic resin composition of the present invention, the blending amount is preferably 0.05 to 2.0 parts by weight per 100 parts by weight of the thermoplastic resin. When the blending amount of the release agent is 0.05 part by weight or more, the effect of improving the release property can be obtained, and when it is 2.0 parts by weight or less, the gas generated from the thermoplastic resin composition can be suppressed, and when the thermoplastic resin composition is mounted on a vehicle as a composite molded article with glass, the transparency of the glass is not reduced, which is preferable.

[0046] In the present invention, any stabilizer used as a stabilizer for thermoplastic resins can be used. Specific examples include antioxidants and light stabilizers. By incorporating these stabilizers, it is possible to obtain a thermoplastic resin composition and a molded article having excellent mechanical properties, moldability, heat resistance, and durability.

[0047] Examples of the antioxidant include phenolic compounds such as 2,6-di-t-butyl-4-methylphenol, tetrakis(methylene-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate)methane, and tris(3,5-di-t-butyl-4-hydroxybenzyl)isocyanurate; sulfur compounds such as dilauryl-3,3′-thiodipropionate and dimyristyl-3,3′-thiodipropionate; and phosphorus compounds such as trisnonylphenyl phosphite and distearyl pentaerythritol diphosphite.

[0048] In the present invention, a phosphorus-based stabilizer may be added as another stabilizer. When a polybutylene terephthalate resin and a polycarbonate resin are selected as the thermoplastic resin (A), the phosphorus-based stabilizer has the effect of suppressing the transesterification reaction between the polybutylene terephthalate resin and the polycarbonate resin, thereby improving moist heat resistance and retention stability. Examples of phosphorus-based stabilizers include phosphate-based stabilizers (phosphate compounds) and phosphite-based stabilizers (phosphite compounds). Two or more of these may be used. Among these, phosphate-based stabilizers are preferred because they are more effective in improving the retention stability of the thermoplastic resin composition. An example of a phosphate-based stabilizer is available under the trade name "ADK STAB" (registered trademark) AX-71 manufactured by ADEKA Corporation.

[0049] For example, additives exemplified as antioxidants may also act as stabilizers or ultraviolet absorbers. Also, some of the additives exemplified as stabilizers may also have antioxidant or ultraviolet absorbing properties. In other words, the above classification is for convenience and does not limit the functions.

[0050] In the present invention, as the end-capping agent, a compound having a reactive group such as an epoxy group, a glycidyl group, an acid anhydride group, a carbodiimide group, or an oxazoline group can be used.

[0051] Examples of the terminal blocking agent include compounds having an epoxy group, such as bisphenol-type epoxy compounds and novolac-type epoxy compounds, and compounds having a carbodiimide group, such as poly(m-phenylenecarbodiimide), poly(tolylcarbodiimide), poly(diisopropylcarbodiimide), poly(methyl-diisopropylphenylenecarbodiimide), poly(triethylphenylenecarbodiimide), poly(triisopropylphenylenecarbodiimide), and poly(diisopropylphenylcarbodiimide). These terminal blocking agents may be used alone or in combination of two or more.

[0052] The method for producing the thermoplastic resin composition of the present invention is not particularly limited as long as it satisfies the requirements of the present invention. A method of uniformly melt-kneading using a single-screw or twin-screw extruder, or a method of mixing in a solution and then removing the solvent, are preferably used. However, from the viewpoint of productivity, a method of uniformly melt-kneading using a single-screw or twin-screw extruder is preferred. A method of melt-kneading using a twin-screw extruder is more preferred in terms of more uniformly melt-kneading (A) the thermoplastic resin and (B) the hydroxyl group-containing (meth)acrylic resin. Among these, a method of melt-kneading using a twin-screw extruder having an L / D ratio > 30, where L (mm) is the screw length and D (mm) is the screw diameter, is particularly preferred. The screw length here refers to the length from the position where the raw materials are supplied at the base of the screw to the tip of the screw. A larger L / D ratio is desirable because it allows (A) the thermoplastic resin and (B) the hydroxyl group-containing (meth)acrylic resin to be thoroughly kneaded, thereby improving the mechanical properties of the thermoplastic resin composition for use in a component bonded to a vehicle window glass with a urethane adhesive.

[0053] Furthermore, when a twin-screw extruder is used to melt-knead the thermoplastic resin composition of the present invention, a combination of full-flight and kneading discs is preferably used as the screw configuration, but one example of obtaining the thermoplastic resin composition of the present invention requires uniform kneading by the screw. Therefore, the ratio of the total length of the kneading discs (kneading zone) to the total length of the screw is preferably in the range of 5 to 50%, more preferably in the range of 10 to 40%.

[0054] When melt-kneading the thermoplastic resin composition of the present invention, a preferred method for feeding each component is to use an extruder having two feeding ports, feed (A) the thermoplastic resin, (B) the hydroxyl group-containing (meth)acrylic resin, and, if necessary, other components through a main feeding port located at the base of the screw, and feed (C) the inorganic filler through a sub-feed port located between the main feeding port and the tip of the extruder, and melt-mix the components.

[0055] The melt-kneading temperature when producing the thermoplastic resin composition of the present invention is preferably 190 to 340°C, more preferably 210 to 310°C, and particularly preferably 240 to 290°C, in terms of excellent moist heat resistance and mechanical properties.

[0056] The thermoplastic resin composition of the present invention can be molded by any conventional method such as injection molding, extrusion molding, blow molding, press molding, spinning, etc., and can be processed into various molded articles for use. Molded articles include injection molded articles, extrusion molded articles, blow molded articles, films, sheets, etc., and films include various types such as unstretched, uniaxially stretched, and biaxially stretched films.

[0057] In the present invention, the above-mentioned various molded articles are suitable for applications in which they are attached to vehicles, taking advantage of their excellent adhesive properties with urethane-based adhesives. Examples of vehicles include automobiles, trains, electric trains, industrial vehicles (forklifts, etc.), and small specialty vehicles (tractors, etc.). The various molded articles are suitable, for example, as glass holder parts and in-vehicle camera bracket parts that require bonding with glass members such as window glass and windshields using a urethane-based adhesive.

[0058] The urethane adhesive of the present invention is not particularly limited, but a one-component or two-component adhesive can be used, in which polyisocyanate is used alone or in a mixture with a compound containing active hydrogen that is easily reactive with isocyanate functional groups (e.g., polyol). Isocyanate functional groups are highly reactive and easily react with active hydrogen on the adhesive surface, resulting in strong adhesive strength due to chemical bonding. A one-component moisture-curing urethane adhesive containing polyisocyanate is preferred, such as "WS-292A" and "WS-242" manufactured by Sika Japan Co., Ltd.

[0059] Molded articles obtained by molding the thermoplastic resin composition of the present invention have excellent adhesion to urethane-based adhesives, and therefore can exhibit the adhesiveness required for components that are directly bonded to vehicle window glass with a urethane-based adhesive, without the need to apply a commonly used primer.

[0060] The present invention will be described in more detail below with reference to examples. The abbreviations and details of the raw materials used in the examples and comparative examples are shown below. Here, "%" and "parts" all mean "% by weight" and "parts by weight", and " / " in the following resin names indicates copolymerization.

[0061] (A) Thermoplastic Resin A-1: ​​Polybutylene terephthalate resin (MFR: 57 g / 10 min (250°C, 1000 gf), carboxyl group amount: 15 eq / t) A-2: Polycarbonate resin ("Iupilon" (registered trademark) S-3000 (product name), manufactured by Mitsubishi Engineering Plastics Corporation, MVR: 14 cm ３ / 10 minutes (300°C / 1.2 kgf)

[0062] (B) Hydroxyl Group-Containing (Meth)acrylic Resins B-1: Hydroxyl group-containing (meth)acrylic resin ("ARUFON" (registered trademark) UH-2170 (trade name) manufactured by Toagosei Co., Ltd. (Mw: 14,000, hydroxyl value: 88 mg KOH / g)) B-2: Hydroxyl group-containing (meth)acrylic resin ("ARUFON" (registered trademark) UH-2041 (Mw: 2,500, hydroxyl value: 120 mg KOH / g) manufactured by Toagosei Co., Ltd.) B'-1: Hydroxyl group-free (meth)acrylic resin ("ARUFON" (registered trademark) UP-1110 (Mw: 2,500) manufactured by Toagosei Co., Ltd.) B'-2: Epoxy group-containing (meth)acrylic resin ("ARUFON" (registered trademark) UG-4070 (Mw: 9700) manufactured by Toagosei Co., Ltd.) B'-3: Mannitol, a type of sugar alcohol (manufactured by Tokyo Chemical Industry Co., Ltd.) (Mw: 182, hydroxyl value: 1850 mgKOH / g)

[0063] (C) Inorganic filler C-1: chopped strand (T-120 (trade name) manufactured by Nippon Electric Glass Co., Ltd., 3 mm length, average fiber diameter 13.0 μm)

[0064] (Other Components) (D) Mold Release Agent D-1: Pentaerythritol tetrastearate ("Roxiol" (registered trademark) VPG861 (trade name) manufactured by Emery Oleochemicals Japan Co., Ltd.) (E) Phosphorus-Based Stabilizer E-1: Phosphate-Based Stabilizer (Approximately equimolar mixture of mono- and di-stearyl acid phosphate) ("ADEKA STAB" (registered trademark) AX-71 (trade name) manufactured by ADEKA Corporation) (F) Crystal Nucleating Agent F-1: Hydrated magnesium silicate (talc) ("Hitron" (trade name) manufactured by Takehara Chemical Industry Co., Ltd.)

[0065] The evaluation methods used in the Examples and Comparative Examples are summarized below. (1) Urethane Adhesion (Urethane Adhesion Strength and Urethane Adhesion Failure Morphology) The thermoplastic resin composition pellets obtained in each Example and Comparative Example were dried for 3 hours in a hot air dryer at 130°C. Then, using an SE100DU injection molding machine manufactured by Sumitomo Heavy Industries, Ltd., a square plate-shaped test specimen (100 mm x 150 mm x 3 mm thick) was molded at a cylinder temperature of 260°C and a mold temperature of 80°C. Both ends of the square plate-shaped test specimen (25 mm x 150 mm x 3 mm thick) were cut off to prepare a rectangular test specimen. A polyurethane adhesive ("WS-292A" manufactured by Sika Japan Co., Ltd.) was uniformly pressure-bonded onto the specimen to a thickness of 3 mm. This specimen was left for 168 hours in an environment of 23±3°C and 50±10% RH, after which a manual peel test was performed in accordance with JASO M338-89. The knife cut interval was 2-3 mm.

[0066] If the adhesive failure mode is cohesive failure, where the adhesive fails at the base material, the urethane adhesiveness can be judged to be good. The cohesive failure rate was calculated using the following formula to evaluate the urethane adhesiveness: Cohesive failure rate (%) = cohesive failure area / adhesive area × 100

[0067] A cohesive failure rate of 90% or more was rated A, 70% or more but less than 90% was rated B, and less than 70% was rated C. In addition, as for the failure mode of the adhesive surface, the state rated A was designated as a cohesive failure mode, the state rated B as a mixed mode of cohesive failure / interfacial peeling, and the state rated C as an interfacial peeling mode. From the viewpoint of the reliability of the adhesive site, a cohesive failure mode is preferable. In other words, a cohesive failure rate of 90% or more was designated as a pass by a rating of A.

[0068] (2) Tensile Properties (Tensile Strength) The pellets obtained in each Example and Comparative Example were dried for 3 hours in a hot air dryer at 130 ° C., and then injection molded using a SE50DUZ injection molding machine manufactured by Sumitomo Heavy Industries, Ltd., at a cylinder temperature of 260 ° C. and a mold temperature of 80 ° C. to form a multipurpose test piece A-type (total length 150 mm, test section width 10 mm, thickness 4 mm) specified in ISO 3167: 2002. Using the obtained multipurpose test piece A-type, the tensile strength was measured according to ISO 527-1, 2: 2012. If the tensile strength was 130 MPa or more, it was judged to be graded A, and if it was less than 130 MPa, it was judged to be graded B.

[0069] [Examples 1 to 10] According to the formulations shown in Table 1, components (A), (B), and all other components were fed into the bottom feed section (main inlet) of a twin-screw extruder, and component (C) was fed into a side inlet located between the main inlet and the tip of the extruder. The mixtures were melt-kneaded in a twin-screw extruder (TEM37SS (trade name), manufactured by Shibaura Machine Co., Ltd.) with a screw diameter of 37 mm and a cylinder temperature set to 260°C. The strands extruded from the die were cooled in a cooling bath and then pelletized with a strand cutter to obtain thermoplastic resin compositions. The resulting thermoplastic resin compositions were evaluated using the above methods, and the results are shown in Table 1. All of the resulting test pieces exhibited excellent urethane adhesion and tensile strength.

[0070] [Comparative Examples 1 to 6] According to the formulations shown in Table 1, components (A), (B)', and all other components were fed into the bottom feed section (main inlet) of a twin-screw extruder, and component (C) was fed into a side inlet located between the main inlet and the tip of the extruder. The resulting mixtures were melt-kneaded in a twin-screw extruder (TEM37SS (trade name), manufactured by Shibaura Machine Co., Ltd.) with a screw diameter of 37 mm and a cylinder temperature set to 260°C. The strands extruded from the die were cooled in a cooling bath and then pelletized with a strand cutter to obtain thermoplastic resin compositions. The resulting thermoplastic resin compositions were evaluated using the above-mentioned methods, and the results are shown in Table 1. All of the resulting test pieces exhibited poor urethane adhesion.

[0071]

[0072] The thermoplastic resin composition and molded article according to the present invention are particularly suitable for use as components to be bonded to vehicle window glass with a urethane adhesive.

Claims

1. A thermoplastic resin composition for components to be bonded to vehicle window glass with a urethane adhesive, comprising 100 parts by weight of (A) thermoplastic resin, 0.1 parts by weight or more and 30 parts by weight or less of (B) hydroxyl group-containing (meth)acrylic resin, and 15 parts by weight or more and 100 parts by weight or less of (C) inorganic filler.

2. The thermoplastic resin composition according to claim 1, wherein the thermoplastic resin (A) comprises a polybutylene terephthalate resin.

3. A thermoplastic resin composition according to claim 1 or 2, wherein the hydroxyl value of (B) the hydroxyl group-containing (meth)acrylic resin is 30 mgKOH / g or more and 500 mgKOH / g or less.

4. The thermoplastic resin composition according to claim 1 or 2, wherein (C) the inorganic filler comprises glass fiber.

5. A molded article made by molding the thermoplastic resin composition according to claim 1 or 2, which is bonded to a vehicle window glass with a urethane adhesive.

6. The molded article according to claim 5, which is directly bonded with a urethane adhesive.

7. A window glass for a vehicle to which the molded product according to claim 5 is bonded with a urethane adhesive.

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