JP7215902B2 - Insert-molded product and method for suppressing deterioration in heat shock resistance of resin composition - Google Patents

Description

The present invention provides an insert molded article having excellent heat shock resistance using a thermoplastic aromatic polyester resin composition containing a colorant, and a decrease in heat shock resistance of the thermoplastic aromatic polyester resin composition containing a colorant. It relates to a suppression method.

Thermoplastic aromatic polyester resins represented by polybutylene terephthalate resin and polyethylene terephthalate resin have various properties such as heat resistance, chemical resistance, electrical properties such as tracking resistance, mechanical properties, and moldability. Are better. Therefore, thermoplastic aromatic polyester resin compositions are widely used as engineering plastics for electronic components such as housings and connectors of electronic devices, automobile components, and the like. These parts are manufactured by insert molding, in which the metal, etc. and the thermoplastic resin are integrally molded by filling the mold with an insert member made of metal, etc., and filling the mold with a thermoplastic resin composition. It is often a product.

However, the coefficient of thermal expansion and contraction due to temperature changes differ greatly between the metals and the like that make up the insert-molded product and the thermoplastic resin composition. A so-called heat shock fracture, in which the molded product is broken, may occur. Heat shock fractures occur particularly at corners of insert members (sharp corners), places with large changes in wall thickness (particularly thin parts), and other places where stress is likely to concentrate in the molded product, as well as inside the mold during insert molding. It tends to occur at places where the strength is lower than other parts, such as the weld line, which is the seam where the resin splits from the insert member and then wraps around the insert member and merges again. Therefore, the thermoplastic aromatic polyester resin composition is required to have heat shock resistance. As a technique for improving the heat shock resistance of a thermoplastic aromatic polyester resin composition, there is a technique of adding an elastomer to the resin composition to relax strain (Patent Documents 1 to 3).
JP-A-3-285945 Japanese Patent Application Laid-Open No. 2001-234046 WO 2009/150831 Pamphlet

By the way, insert-molded articles used as electronic parts and automobile parts are often colored black using a coloring agent such as carbon black. The present inventors have found that black-colored insert-molded articles tend to have lower heat shock resistance than uncolored insert-molded articles. Accordingly, the present inventors have made extensive research on methods for preventing deterioration in the heat shock resistance of insert-molded articles colored black or the like. Then, as a coloring agent such as carbon black used for coloring the resin, a coloring agent having an average primary particle size of 25 nm or more is added to the thermoplastic aromatic polyester resin to be colored, thereby producing a colored thermoplastic aromatic resin. In the group polyester resin composition, it was found that the deterioration of the heat shock resistance compared to the uncolored product can be suppressed, and in particular, a high effect can be obtained in the insert-molded product in which the insert member is a flat plate. Arrived.

An object of the present invention is to provide an insert-molded article having excellent heat shock resistance using a thermoplastic aromatic polyester resin composition containing a colorant. Another object of the present invention is to provide a method for suppressing deterioration in heat shock resistance of a thermoplastic aromatic polyester resin composition containing a colorant.

The insert-molded article according to the present invention has a resin member and an insert member, and the resin member is a thermoplastic aromatic polyester containing a thermoplastic aromatic polyester resin A and a coloring agent B having an average primary particle size of 25 nm or more. An insert-molded product containing a resin composition and having excellent heat shock resistance.

In the present invention, the content of the colorant B in the thermoplastic aromatic polyester resin composition is preferably 0.05% by mass or more and 5.0% by mass or less. Moreover, it is preferable that the thermoplastic aromatic polyester resin A contains a polybutylene terephthalate-based resin.

In the present invention, the colorant B can be configured to contain an inorganic pigment or an organic pigment. Also, the colorant B can be configured to contain a black pigment, a red pigment, an orange pigment, or a white pigment. Colorant B preferably contains carbon black or carbon nanotubes. The average primary particle size of the colorant B is preferably 27 nm or more and 50 nm or less.

In the present invention, the insert member is preferably a plate member containing metal, alloy or inorganic solid matter. Further, the insert member has a main surface having a longitudinal direction and a width direction, and the ratio of the maximum width to the maximum thickness is 2 or more in a cross section taken along a plane perpendicular to the longitudinal direction. can do. The thickness of the insert member can be 0.1 mm or more and 3 mm or less.

In the present invention, at least a portion of the insert member is covered with a resin member, and the thickness of the resin member at the covered portion can be 0.3 mm or more and 5 mm or less.

The method for suppressing deterioration of heat shock resistance according to the present invention is a resin composition containing a coloring agent, in which a coloring agent B having an average primary particle size of 25 nm or more is blended with a thermoplastic aromatic polyester resin A for an insert-molded product. This is a method for suppressing deterioration of heat shock resistance.

ADVANTAGE OF THE INVENTION According to this invention, the insert-molded article excellent in heat shock resistance using the thermoplastic aromatic polyester resin composition containing a coloring agent can be provided. In particular, when a plate-like insert member is used, it is possible to provide an insert-molded product in which deterioration of the heat shock resistance of the resin portion containing the thermoplastic aromatic polyester resin composition is suppressed. Moreover, it is possible to provide a method for suppressing deterioration in heat shock resistance of a thermoplastic aromatic polyester resin composition containing a colorant.

It is a figure which shows the test piece used by the heat-shock resistance test, Comprising: (A) is a perspective view, (B) is a top view. 1. It is a figure which shows the insert member of the test piece shown in FIG. 1, (A) is a perspective view, (B) is a top view. FIG. 1 shows a test piece used in a heat shock resistance test, where (A) is a top view, (B) is a cross-sectional view taken along line BB in (A), and (C) is It is a cross-sectional view taken along line CC in (A). FIG. 4 is a top view showing an insert member used in the test piece shown in FIG. 3; FIG. 1 shows a test piece used in a heat shock resistance test, where (A) is a top view, (B) is a cross-sectional view taken along line BB in (A), and (C) is It is a cross-sectional view taken along line CC in (A). FIG. 6 is a top view showing an insert member used in the test piece shown in FIG. 5;

An embodiment of the present invention will be described in detail below. The present invention is not limited to the following embodiments, and can be implemented with appropriate modifications within the scope that does not impair the effects of the present invention.

[Insert molded product]
The insert-molded product of this embodiment has a resin member and an insert member. Hereinafter, the resin member and the insert member will be described in this order.

(Resin member)
The resin member is formed using a thermoplastic aromatic polyester resin composition (hereinafter also referred to as "resin composition") containing a thermoplastic aromatic polyester resin A and a coloring agent B having an average primary particle size of 25 nm or more. and comprising the resin composition. Although this resin member is colored, deterioration in heat shock resistance is suppressed. Therefore, an insert-molded article having this resin member is excellent in heat shock resistance.

(Thermoplastic aromatic polyester resin A)
The thermoplastic aromatic polyester resin A is a resin colored with a coloring agent. The thermoplastic aromatic polyester resin A is a reaction between a dicarboxylic acid component mainly composed of a dicarboxylic acid compound and/or an ester-forming derivative thereof and a diol component mainly composed of a diol compound and/or an ester-forming derivative thereof. It is a thermoplastic polyester resin obtained by the above method, and contains an aromatic compound in at least one of the dicarboxylic acid component and the diol component.

Dicarboxylic acid components include, for example, aliphatic dicarboxylic acids (e.g., succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedicarboxylic acid, dothecanedicarboxylic acid, hexadecanedicarboxylic acid, dimer C _4-40 dicarboxylic acid, preferably C _4-14 dicarboxylic acid, etc.), alicyclic dicarboxylic acid (e.g., hexahydrophthalic acid, hexahydroisophthalic acid, hexahydroterephthalic acid, hymic acid, etc.) dicarboxylic acids of about C _4-40 , preferably dicarboxylic acids of about C _8-12 ), aromatic dicarboxylic acids (e.g., phthalic acid, isophthalic acid, terephthalic acid, methylisophthalic acid, methylterephthalic acid, 2,6- Naphthalenedicarboxylic acids such as naphthalenedicarboxylic acid, 4,4'-biphenyldicarboxylic acid, 4,4'-diphenoxyetherdicarboxylic acid, 4,4'-dioxybenzoic acid, 4,4'-diphenylmethanedicarboxylic acid, 4,4 C _8-16 dicarboxylic acids such as '-diphenylketonedicarboxylic acid), or derivatives thereof (for example, ester-forming derivatives such as lower alkyl esters, aryl esters and acid anhydrides). These dicarboxylic acid components can be used alone or in combination of two or more. Preferred dicarboxylic acid components include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid and naphthalenedicarboxylic acid (particularly terephthalic acid and 2,6-naphthalenedicarboxylic acid). The dicarboxylic acid component preferably contains, for example, 50 mol % or more, preferably 80 mol % or more, and more preferably 90 mol % or more of aromatic dicarboxylic acid. Furthermore, if necessary, polyvalent carboxylic acids such as trimellitic acid and pyromellitic acid or their ester-forming derivatives (alcohol esters, etc.) may be used in combination. A branched thermoplastic polyester resin can also be obtained by using such a polyfunctional compound in combination.

Examples of diol components include aliphatic alkanediols (e.g., ethylene glycol, trimethylene glycol, propylene glycol, 1,4-butanediol, 1,3-butanediol, neopentyl glycol, hexanediol, octanediol, decanediol, aliphatic diols of about C _2-12 , preferably aliphatic diols of about C _2-10 ), polyoxyalkylene glycols (glycols which are about C _2-4 alkylene groups and have a plurality of oxyalkylene units, (e.g., diethylene glycol, dipropylene glycol, ditetramethylene glycol, triethylene glycol, tripropylene glycol, polytetramethylene glycol, etc.), alicyclic diols (e.g., 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, hydrogenated bisphenol A, etc.). Aromatic diols such as hydroquinone, resorcinol, bisphenol, 2,2-bis(4-hydroxyphenyl)propane, 2,2-bis-(4-(2-hydroxyethoxy)phenyl)propane, and xylylene glycol can also be used in combination. You may These diol components can be used alone or in combination of two or more. Preferred diol components include C _2-10 alkylene glycols (linear alkylene glycols such as ethylene glycol, trimethylene glycol, propylene glycol, 1,4-butanediol) and the like. The diol component preferably contains, for example, 50 mol % or more, preferably 80 mol % or more, more preferably 90 mol % or more of C _2-10 alkylene glycol. Furthermore, if necessary, a polyol such as glycerin, trimethylolpropane, trimethylolethane, pentaerythritol, or an ester-forming derivative thereof may be used in combination. A branched thermoplastic polyester resin can also be obtained by using such a polyfunctional compound in combination.

As the thermoplastic aromatic polyester resin A, copolyesters obtained by combining two or more of the above-described dicarboxylic acid components and diol components, and other copolymerizable monomers (hereinafter sometimes referred to as copolymerizable monomers), A copolyester in which an oxycarboxylic acid component, a lactone component, etc. are combined can also be used.

Oxycarboxylic acids (or oxycarboxylic acid components or oxycarboxylic acids) include, for example, oxycarboxylic acids such as oxybenzoic acid, oxynaphthoic acid, hydroxyphenylacetic acid, glycolic acid, oxycaproic acid, and derivatives thereof. . Lactones include C _3-12 lactones such as propiolactone, butyrolactone, valerolactone, caprolactone (eg, ε-caprolactone, etc.) and the like.

In the copolyester, the proportion of the copolymerizable monomer can be selected, for example, from a range of about 0.01 mol% to 30 mol%, usually about 1 mol% to 30 mol%, preferably 3 mol%. It is about 25 mol % or less, more preferably about 5 mol % or more and 20 mol % or less. Further, when homopolyester and copolyester are used in combination, the proportion of homopolyester and copolyester is such that the proportion of copolymerizable monomers is 0.1 mol% or more and 30 mol% or less with respect to all monomers. (Preferably about 1 mol% to 25 mol%, more preferably about 5 mol% to 25 mol%), usually homopolyester / copolyester = 99/1 to 1/99 (mass ratio ), preferably 95/5 to 5/95 (mass ratio), more preferably 90/10 to 10/90 (mass ratio).

A preferred thermoplastic aromatic polyester resin A is a homopolyester or copolyester containing alkylene arylate units such as alkylene terephthalate and alkylene naphthalate as a main component (for example, about 50 to 100 mol%, preferably about 75 to 100 mol%). [For example, polyalkylene terephthalate (e.g., poly C _2-4 alkylene terephthalate such as polyethylene terephthalate (PET), polytrimethylene terephthalate (PTT), polybutylene terephthalate (PBT)), 1,4-cyclohexanedimethylene terephthalate (PCT ), homopolyesters such as polyalkylene naphthalates (e.g., poly C _2-4 alkylene naphthalates such as polyethylene naphthalate, polypropylene naphthalate, polybutylene naphthalate); alkylene terephthalate and/or alkylene naphthalate units as main components ( for example, 50 mol % or more)], and these can be used singly or in combination of two or more.

A particularly preferred thermoplastic aromatic polyester resin A contains ₈₀ mol% or more (especially 90 mol% or more ) containing homopolyester resins or copolyester resins (eg, polyethylene terephthalate resins, polytrimethylene terephthalate resins, polybutylene terephthalate resins, polytetramethylene-2,6-naphthalenedicarboxylate resins, etc.).

Among these, polyethylene terephthalate resin and polybutylene terephthalate resin are preferred, and polybutylene terephthalate resin is particularly preferred.

The amount of terminal carboxyl groups in the thermoplastic aromatic polyester resin A is not particularly limited as long as it does not impair the effects of the present invention. The terminal carboxyl group content of the thermoplastic aromatic polyester resin A is preferably 30 meq/kg or less, more preferably 25 meq/kg or less.

The intrinsic viscosity (IV) of the thermoplastic aromatic polyester resin A is not particularly limited as long as it does not impair the effects of the present invention. The intrinsic viscosity of the thermoplastic aromatic polyester resin A is preferably 0.60-1.30 dL/g. It is more preferably 0.65 to 1.20 dL/g from the viewpoint of improving moldability and heating/cooling durability. When the thermoplastic aromatic polyester resin A having an intrinsic viscosity within this range is used, the colorant composition B can be blended more uniformly. Further, thermoplastic aromatic polyester resins A having different intrinsic viscosities can be blended to adjust the intrinsic viscosity. For example, by blending a thermoplastic aromatic polyester resin A having an intrinsic viscosity of 1.0 dL / g and a thermoplastic aromatic polyester resin A having an intrinsic viscosity of 0.8 dL / g, a thermoplastic resin having an intrinsic viscosity of 0.9 dL / g Aromatic polyester resin A can be prepared. The intrinsic viscosity (IV) of the thermoplastic aromatic polyester resin A can be measured, for example, in o-chlorophenol at a temperature of 35°C.

The blending amount of the thermoplastic aromatic polyester resin A can be, for example, 40% by mass or more and 99% by mass or less, preferably 50% by mass or more and 90% by mass or less in the total resin composition. When the blending amount of the thermoplastic aromatic polyester resin A is within this range, the properties of the thermoplastic aromatic polyester resin A are fully exhibited, and electrical properties such as heat resistance, chemical resistance, and tracking resistance, mechanical properties, etc. It is possible to obtain a resin composition excellent in various properties such as properties and moldability.

As the thermoplastic aromatic polyester resin A, a commercially available product may be used, and a dicarboxylic acid component or a reactive derivative thereof, a diol component or a reactive derivative thereof, and, if necessary, a (polycondensation) by a method such as transesterification or direct esterification.

(Colorant B)
Colorant B can be selected from known colorants depending on the color required for the molded product. Examples of the coloring agent B include powdery or particulate coloring agents such as inorganic pigments, organic pigments, and dyes. Examples of inorganic pigments include carbon black (e.g., acetylene black, lamp black, thermal black, furnace black, channel black, ketjen black, etc.), black pigments such as carbon nanotubes, red pigments such as iron oxide red, and molybdate. Examples include orange pigments such as orange, white pigments such as titanium oxide, and the like. Examples of organic pigments include yellow pigments, orange pigments, red pigments, blue pigments, green pigments, and the like. These coloring agents B can be used alone or in combination of two or more. Further, the coloring agent B may be one whose surface has been treated with an acid or the like. Note that when an organic pigment or dye is used as the colorant B, the heat shock resistance tends to decrease less than when the inorganic pigment is used. The effect of suppressing the decrease in shock resistance is more likely to be obtained.

The average primary particle size of Colorant B is 25 nm or more. By setting the average primary particle diameter of the coloring agent B to 25 nm or more, the deterioration of the heat shock resistance compared to the uncolored product can be suppressed regardless of whether the shape of the insert member is a square prism or a plate. can. In particular, it is possible to suppress deterioration of heat shock resistance even in an insert-molded article using a plate-shaped insert member, which is difficult to suppress deterioration of heat shock resistance as compared with an uncolored article. The average primary particle size of the colorant B is preferably 25 nm or more and 50 nm or less, more preferably 27 nm or more and 40 nm or less, and particularly preferably 28 nm or more and 35 nm or less. If the average primary particle size of the colorant B exceeds 50 nm, the mechanical properties of the thermoplastic aromatic polyester resin composition may deteriorate. The average primary particle size of the colorant B is the arithmetic mean particle size obtained by electron microscopic observation of 1000 particles of the colorant B before being blended in the resin composition.

The content of the colorant B in the entire thermoplastic aromatic polyester resin composition is preferably 0.05% by mass or more and 5.0% by mass or less, and 0.1% by mass or more and 3.0% by mass or less. more preferably 0.2% by mass or more and 1.0% by mass or less. By setting the content of the colorant B to 0.1% by mass or more and 5.0% by mass or less relative to the total resin composition, the molded article can be colored with sufficient brightness and chromaticity. When carbon black is used as the colorant B, the thermoplastic aromatic polyester resin composition capable of forming a molded article having excellent jetness can be obtained by adjusting the content as described above.

The colorant B is a masterbatch containing, if necessary, other resins such as polyester resins such as thermoplastic aromatic polyester resin A, thermoplastic resins such as styrene resins and acrylic resins, and thermosetting resins. can also be In addition, various additives such as stabilizers (antioxidants, ultraviolet absorbers, heat stabilizers, etc.), flame retardants, lubricants, release agents, antistatic agents, dispersants, plasticizers, A nucleating agent or the like may be added. The content of the additive in this case can be, for example, more than 0% by mass and 20% by mass or less in the masterbatch.

The masterbatch containing the colorant B can be produced by kneading the base resin and the colorant B by a conventional method. For example, the base resin, colorant B, and other additives are put into a stirrer and uniformly mixed, and then melted and kneaded with an extruder. The resulting masterbatch can be in various forms such as powders, pellets and strips.

(Other compounding agents)
Various additives can be added to the thermoplastic aromatic polyester resin composition of the present embodiment. For example, an elastomer can be blended for the purpose of further enhancing heat shock resistance.

Examples of elastomers include olefin-based elastomers, vinyl chloride-based elastomers, styrene-based elastomers, polyester-based elastomers, butadiene-based elastomers, urethane-based elastomers, polyamide-based elastomers, silicone-based elastomers, and core-shell-based elastomers. Specifically, ethylene ethyl acrylate (EEA)-based copolymers, methacrylic acid ester-butylene-styrene (MBS)-based copolymers, ethylene glycidyl methacrylate (EGMA)-based copolymers, polytetramethylene glycol (PTMG) A polyester elastomer or the like can be used. Examples of ethylene ethyl acrylate (EEA) copolymers include graft copolymers of ethylene ethyl acrylate and butyl acrylate and/or methyl methacrylate.

The amount of the elastomer compounded is preferably 1% by mass or more and 30% by mass or less, more preferably 5% by mass or more and 20% by mass or less, in the thermoplastic aromatic polyester resin composition. By blending 1% by mass or more and 30% by mass or less of the elastomer in the thermoplastic aromatic polyester resin composition, the resin has further excellent heat shock resistance without impairing the mechanical properties of the thermoplastic aromatic polyester resin composition. It can be a composition.

Moreover, an inorganic filler can be blended for the purpose of improving the mechanical properties of the resulting molded article. Examples of inorganic fillers include fibrous fillers, plate-like fillers, and particulate fillers. Examples of fibrous fillers include glass fiber, asbestos fiber, carbon fiber, silica fiber, alumina fiber, silica-alumina fiber, aluminum silicate fiber, zirconia fiber, potassium titanate fiber, silicon carbide fiber, whisker (silicon carbide, whiskers such as alumina and silicon nitride); organic fibers such as fibers made of aliphatic or aromatic polyamide, aromatic polyester, fluororesin, acrylic resin such as polyacrylonitrile, and rayon; . Plate-like fillers include, for example, talc, mica, glass flakes, graphite and the like. Examples of powdery fillers include glass beads, glass powder, milled fibers (eg, milled glass fibers), wollastonite (wollastonite), and the like. The wollastonite may be plate-like, column-like, fiber-like, or the like. Among these inorganic fillers, glass fiber is preferable because it is inexpensive and readily available.

The fibrous filler has an average diameter of, for example, 1 μm to 30 μm (preferably 5 μm to 20 μm, more preferably 10 to 15 μm), and an average length of, for example, 100 μm to 5 mm (preferably 300 μm to 4 mm, more preferably 500 μm). up to 3.5 mm). The average primary particle size of the plate-like or powdery granular filler can be, for example, about 0.1 μm to 500 μm, preferably about 1 μm to 100 μm. These inorganic fillers can be used alone or in combination of two or more. The average diameter and average length of the fibrous filler and the average primary particle diameter of the plate-like or powdery or granular filler are the fibrous filler, the plate-like or powdery or granular filler before being blended in the resin composition. is a value calculated by weighted average after analyzing images taken with a CCD camera. These can be calculated using, for example, a dynamic image analysis method/particle (state) analyzer PITA-3 manufactured by Seishin Enterprise Co., Ltd. The aspect ratio of the plate-like or powdery filler is not particularly limited, and can be, for example, 1 or more and 10 or less.

The content of the inorganic filler is preferably 10% by mass or more and 50% by mass or less, more preferably 15% by mass or more and 40% by mass or less, and still more preferably 20% by mass or more in the total thermoplastic aromatic polyester resin composition. It can be 35% by mass or less.

In addition, the thermoplastic aromatic polyester resin composition contains stabilizers (antioxidants, ultraviolet absorbers, heat stabilizers, etc.), flame retardants, lubricants, release agents, antistatic agents, dispersants, plasticizers, nuclei agents, fluidity improvers and the like may be added. The content of the additive in this case can be, for example, more than 0% by mass and 20% by mass or less in the total thermoplastic aromatic polyester resin composition.

Epoxy compounds such as bisphenol A type epoxy compounds and novolak type epoxy compounds may be added to the thermoplastic aromatic polyester resin composition in order to improve hydrolysis resistance, heat shock resistance and the like. If necessary, it may be used in combination with other resins (thermoplastic resins such as styrene resins and acrylic resins, thermosetting resins, etc.).

The thermoplastic aromatic polyester resin composition can achieve both sufficient colorability and heat shock resistance. For example, in a molded article made of a resin composition colored black using carbon black as the coloring agent B, the L ^* value (brightness) in the L ^* a ^* b ^* color system measured in accordance with JIS Z8729:2004. is 25 or less (preferably 20 or less, more preferably 15 or less, and particularly preferably 10 or less). In addition, in a cycle test in which the cycle of cooling at -40 ° C. for 1.5 hours and heating at 180 ° C. for 1.5 hours is repeated, the number of cycles until cracks occur in the molded product. Less degradation to molded parts is possible.

Therefore, this thermoplastic aromatic polyester resin composition can be suitably used as a resin composition for colored insert-molded articles. A colored insert-molded article made of this resin composition has sufficient coloring properties (brightness, chroma, or jetness), and is resistant to heat shock fracture even when used in an environment with large temperature changes. can be prevented from occurring. In particular, in an insert-molded product using a plate-like insert member, the effect of preventing heat shock fracture is more likely to be obtained.

"Heat shock resistance" is the ability to prevent breakage of an insert-molded product due to temperature changes when the product is used in an environment with large temperature changes. Impact resistance that prevents the molded product from breaking due to physical impact, toughness represented by tensile fracture strain (elongation), etc. When used at high temperatures, the molded product deforms or resin It is a performance different from the heat resistance that prevents the composition from deteriorating. Moreover, it is clear from a comparison between Reference Example 1 and Comparative Examples, which will be described later, that there is no correlation between the heat shock resistance and the mechanical strength. That is, in comparison between the non-colored molded article and the colored molded article, the heat shock resistance of the colored molded article was remarkably lowered compared to the difference in mechanical strength. Furthermore, the tendency of decrease in mechanical strength in each resin composition of Examples and Comparative Examples does not necessarily coincide with the tendency of decrease in heat shock resistance, and that the plate-shaped insert member and the quadrangular prism-shaped insert member are both heat resistant. It was confirmed that the tendencies of shockability were different.

The method for obtaining the thermoplastic aromatic polyester resin composition is not particularly limited. For example, the thermoplastic aromatic polyester resin A, the colorant B and, if necessary, other compounding agents are mixed in various forms such as powder, pellets, and flakes, and if necessary, are premixed and then fed into a melt-kneader. . Subsequently, the thermoplastic aromatic polyester resin A, the colorant B, and other compounding agents are blended by heating to the melting point of the thermoplastic aromatic polyester resin A or higher and melt-kneading.

(Insert member)
The insert member is preferably a plate member made of metal, alloy or inorganic solid. Among them, those that do not deform or melt when in contact with the resin during molding are preferred. Examples include metals such as aluminum, magnesium, copper, and iron, alloys of the above metals such as brass, and inorganic solids such as glass and ceramics. things can be mentioned.

The shape of the insert member is not particularly limited, and various shapes such as a square prism shape and a plate shape can be used. In particular, those having a main surface having a longitudinal direction and a width direction, and having a ratio of the maximum value of width to the maximum value of thickness of 2 or more in a cross section cut along a plane perpendicular to the longitudinal direction of the plate (for example, a wiring material such as a bus bar) is preferable. The thickness of the plate-like insert member is preferably 0.1 mm or more and 3 mm or less (for example, 0.5 mm or more and 2 mm or less). The cross-sectional shape of the plate-like insert member is not particularly limited, and may be elliptical, rectangular, polygonal, or the like.

(Insert molded product)
The shape and size of the insert-molded product are not particularly limited, and can be shaped according to the application. In particular, the thermoplastic aromatic polyester resin composition described above is excellent in heat shock resistance while maintaining colorability. It is possible to obtain a molded product having excellent resistance, and it is possible to prevent the occurrence of heat shock fracture. In the insert-molded product, for example, when at least a part of the insert member is covered with a resin member, the thickness of the resin portion covering the insert member is 0.3 mm or more and 5 mm or less (for example, 0.5 mm or more and 3 mm or less). It can be an insert-molded product having a thin portion.

Here, the thickness of the resin portion covering the insert member means the thickness of the resin member in the covering portion in the portion where the resin member of the insert-molded article covers the insert member, and the surface of the resin member in the covering portion. , refers to the length perpendicular to the face of the insert immediately below. For example, FIG. 3 shows an example of an insert-molded product used in the examples. In the insert-molded product (test piece 20) in FIG. 3, the length T in the vertical direction from the surface of the resin member 21 in the covering portion where the resin member 21 covers the insert member 22 to the surface of the insert member 22 immediately below is the insert This is the thickness of the resin portion covering the member 22 (FIG. 3(C)). In addition, a plurality of insert members may be laminated and inserted into one insert-molded product with a layer of a resin member interposed therebetween. In that case, the thickness of the resin part is the thickness from the surface of the resin member of the insert molded product to the insert member immediately below (the outermost layer), and the thickness of the layer of the resin member sandwiched between each insert member. However, if any one of the thicknesses of the resin portion is within the thickness range of the resin portion, it is desirable to consider the heat shock resistance of the resin portion. . Also, if the ratio of the resin portion is extremely high (the insert member is too thin), the insert member may be deformed due to shrinkage of the resin portion. From the viewpoint that the fluidity of the resin may be insufficient and molding defects may occur, the ratio of the thickness of the resin portion to the thickness of the insert member is 1:8 to 8. :1, more preferably 1:5 to 5:1.

The method for producing an insert-molded article is not particularly limited. For example, the above-described thermoplastic aromatic polyester resin composition and an insert member pre-molded into a desired shape are used, and the insert member is attached in advance to a mold. , the resin composition can be filled on the outside thereof by injection molding, extrusion compression molding, or the like, and composite molding can be performed.

EXAMPLES The present invention will be described in more detail with reference to examples below, but the interpretation of the present invention is not limited by these examples.

[Reference Example 1, Example 1, Comparative Examples 1 to 4]
Using the materials shown below, the content ratios shown in Tables 1 and 2 were kneaded at 250 ° C. by a twin-screw extruder (manufactured by The Japan Steel Works, Ltd., cylinder diameter 30 mmφ), Reference Example 1, Example 1 and comparison Thermoplastic aromatic polyester resin composition pellets of Examples 1 to 4 were produced. Incidentally, Reference Example 1 is an example of an uncolored resin composition, and Example 1 and Comparative Examples 2 to 4 are examples in which the colorant B is directly added to the thermoplastic aromatic polyester resin A. . Further, in Comparative Example 1, a masterbatch was prepared by previously melt-kneading the colorant B in the thermoplastic polyester resin A so that the concentration thereof was 20% by mass, and the masterbatch was added to 2.5% of the total resin composition. This is an example in the case of adding colorant B in an amount of 0.5% by mass in the entire resin composition.

(Thermoplastic aromatic polyester resin)
Thermoplastic aromatic polyester resin A: Polybutylene terephthalate resin (PBT) with an intrinsic viscosity of 0.68 dL / g manufactured by Wintech Polymer Co., Ltd.
(coloring agent)
Carbon black 1: manufactured by Wilbur-Ellis Co., carbon black with an average primary particle size of 30 nm Carbon black 2: manufactured by Mitsubishi Chemical Corporation, carbon black with an average primary particle size of 22 nm Carbon black 3: manufactured by Wilbur-Ellis Co., average primary Carbon black with a particle size of 13 nm Carbon black 4: Carbon black with an average primary particle size of 13 nm (surface acid-treated product) manufactured by Wilbur Ellis Co., Ltd.

(Inorganic filler)
Glass fiber: manufactured by Nippon Electric Glass Co., Ltd., trade name “ECS03T-187”, average diameter 13 μm
(elastomer)
Ethylene ethyl acrylate (EEA)-based elastomer: manufactured by NOF Corporation, trade name "Modiper A5300", 70% by mass of ethylene ethyl acrylate (EEA) as a copolymer component, random copolymer of butyl acrylate and methyl methacrylate (BA- stat-MMA) in an amount of 30% by mass.

<Evaluation>
[Heat shock resistance]
Heat shock resistance was evaluated in the following manner for each of the cases of using the square prism-shaped, L-shaped plate-shaped, or I-shaped plate-shaped insert member.

(Heat shock resistance when square columnar insert member is used)
Using the thermoplastic aromatic polyester resin composition pellets obtained in Reference Example 1, Example 1 and Comparative Examples 1 to 4, and a quadrangular prism-shaped metal insert member, the test pieces shown in FIGS. 1 and 2 were obtained by injection molding. was insert-molded and the heat shock resistance was evaluated. FIG. 1 is a diagram showing an insert-molded test piece 10, and FIG. 2 is a diagram showing an insert member 2. As shown in FIG. As shown in FIG. 1, the test piece 10 is obtained by embedding a metallic square-pillar-shaped insert member 2 in a square-pillar-shaped resin member 1 containing a thermoplastic aromatic polyester resin composition. The resin member 1 is molded using the resin composition pellets obtained as described above. Using the above pellets dried at 140 ° C. for 3 hours, a test piece molding mold (22 mm × 22 mm × height 28 mm) was prepared at a resin temperature of 260 ° C., a mold temperature of 65 ° C., an injection time of 25 seconds, and a cooling time of 10 seconds. A mold for inserting an insert member having a quadrangular prism-shaped portion of at least 14 mm × 14 mm × height 24 mm inside the square prism-shaped resin part), the thickness of a part of the resin part is 1 mm as a minimum thickness A test piece was manufactured by insert injection molding as follows. As shown in FIG. 2, the insert member 2 has a quadrangular prism-shaped upper portion 2a, a quadrangular prism-shaped lower portion 2b, and a columnar constricted portion 2c connecting them between them. The insert member 2 has a lower portion 2b and a constricted portion 2c embedded in the resin member 1, and an upper portion 2a exposed from the upper surface of the resin member 1 (see FIG. 1A). Furthermore, as shown in FIG. 1B, the corners of the resin member 1 and the corners of the insert member 2 are arranged so as to be positioned in different directions. That is, the corners of the insert member 2 are arranged so as to face the side surfaces of the resin member 1 . The distance between the tip of the corner of the insert member 2 and the side surface of the resin member 1 is approximately 1 mm. The resin member 1 has a thin portion in the vicinity of the tip of the corner (sharp corner) of the insert member 2 . In injection molding of the resin member 1, the gate for filling the mold with the melted resin composition pellets is a 1 mmφ pin gate in the center of the bottom surface (22 mm × 22 mm surface) of the resin member 1. is provided. Therefore, the molten resin composition injected from the gate flows along the bottom surface of the resin member 1 and then fills the space in the mold along the insert member 2 . At this time, the thick part where the molten resin composition flows easily is filled first, and the thin part is delayed in filling. A weld portion is formed (near the tip of the corner of the insert member 2).
Using a thermal shock tester (manufactured by Espec Co., Ltd.), the above test piece 10 was repeatedly cooled at -40 ° C. for 1.5 hours and then heated at 180 ° C. for 1.5 hours. The weld part was observed every time. The number of cycles at which cracks occurred in the weld portion was evaluated as an index of heat shock resistance. The results are shown in Tables 1 and 2.

(Heat shock resistance when L-shaped plate-like insert member is used)
Using the thermoplastic aromatic polyester resin compositions obtained in Reference Example 1, Example 1 and Comparative Examples 1, 2, and 4, and an L-shaped plate-shaped metal insert member, injection molding was performed to The test piece shown in 1 was insert-molded and the heat shock resistance was evaluated. FIG. 3 is a diagram showing an insert-molded test piece 20, (A) is a top view, (B) is a cross-sectional view taken along line BB in (A), and (C) is ( FIG. 2A is a cross-sectional view taken along line CC in FIG. 4A and 4B are diagrams showing the insert member 22. FIG. The resin member 21 is molded using the resin composition pellets obtained as described above. Using the pellets dried at 140 ° C. for 3 hours, a test piece molding mold [width w ₁ 25 mm × L ₁ Inside an L-shaped plate-shaped resin part of 70 mm × L ₂ 70 mm, thickness t ₁ 3.6 mm, width w ₂ 21 mm × L ₃ 90 mm × L ₄ 90 mm, thickness t ₂ 1.6 mm (cross-sectional width w ₂ /thickness t ₂ ratio is 13.1) Insert injection molding into a mold for inserting an L-shaped iron plate] so that the thickness T of a part of the resin part is 1 mm as the minimum wall thickness and test A piece 20 was produced. In FIG. 3, L ₅ and L ₆ are 92 mm. Two holes h ₁ and h ₂ near both ends of the L-shaped plate-shaped insert member shown in FIG. In the hole h3 of the resin member 21 shown in FIG. ₃ , the L-shaped plate-shaped insert member 22 is fixed by pressing it with a pin in the mold. It is formed by flowing. Also, in FIG. 3A, the position of the side gate S ₁ (width: 4 mm, thickness: 3 mm) filled with resin is indicated by a dashed line. The side gate S1 is located above the resin portion 21 at _{a distance d1 of 1 mm} from the lower end of the right side surface. That is, in the resin member 21 of the test piece 20 , welded portions are generated at the confluence portion where the flowing resin wraps around the insert member 22 and the merge portion where the pin that presses the insert member 22 wraps around.
The resulting test piece 20 is heated at 140°C for 1 hour and 30 minutes using a thermal shock tester, then cooled to -40°C for 1 hour and 30 minutes, and then heated to 140°C. A heat shock resistance test was carried out with 1 cycle, and the number of cycles until cracks occurred in the molded product was measured, and the average rupture life of five samples was evaluated as heat shock resistance.

(Heat shock resistance when I-shaped plate-shaped insert member is used)
Using the thermoplastic aromatic polyester resin compositions obtained in Reference Example 1, Example 1 and Comparative Examples 1 to 4, and an I-shaped plate-shaped metal insert member, injection molding is performed as shown in FIGS. A test piece was insert-molded and evaluated for heat shock resistance. FIG. 5 is a diagram showing an insert-molded test piece 30, (A) is a top view, (B) is a cross-sectional view taken along line BB in (A), and (C) is ( FIG. 2A is a cross-sectional view taken along line CC in FIG. FIG. 6 is a diagram showing the insert member 32. As shown in FIG. The resin member 31 is molded using the resin composition pellets obtained as described above. Using the pellets dried at 140 ° C. for 3 hours, a test piece molding mold [width w ₁₁ 25 mm × L ₁₁ Inside an I-shaped resin plate having a width of 120 mm and a thickness of t ₁₁ of 4 mm, a width w ₁₂ of 20 mm × L ₁₂ of 150 mm and a thickness of t ₁₂ of 1.6 mm (cross-sectional width w ₁₂ /thickness t ₁₂ ratio of 12.0 mm) was placed. 5) Mold for inserting I-shaped iron plate], insert injection molding was performed so that the minimum thickness of a part of the resin portion was 1.2 mm, and a test piece 30 was manufactured. Two holes h ₁₁ and h ₁₂ near both ends of the I-shaped insert member 32 are for fixing the insert member 32 by fitting pins in the mold. _In the hole h13 of the resin member 31 shown in FIG. 5, the I-shaped plate-shaped insert member 32 is fixed by pressing it with a pin in the mold. It is formed by flowing. The diameter _d12 of the hole h13 is ₄ mm. _Around the hole h13, the thickness t13 of the resin member 31 is 3 mm within a range of L14 of ₁₅ mm and _L15 of ₁₀ mm. In addition, in FIG. 5A, the position of the side gate S ₁₁ (width: 4 mm, thickness: 3 mm) to be filled with resin is indicated by a dashed line. is located on the right side where the distance d11 from is ₁ mm. That is, in the resin member 21 of the test piece 20 , welded portions are generated at the confluence portion where the flowing resin wraps around the insert member 22 and the merge portion where the pin that presses the insert member 22 wraps around.
The resulting test piece 30 is heated at 140°C for 1 hour and 30 minutes using a thermal shock tester, then cooled to -40°C for 1 hour and 30 minutes, and then heated to 140°C. A heat shock resistance test was carried out with 1 cycle, and the number of cycles until cracks occurred in the molded product was measured, and the average rupture life of five samples was evaluated as heat shock resistance.

[Tensile strength and tensile breaking strain]
After drying the obtained pellets at 140°C for 3 hours, an ISO 1A type tensile test piece was produced by injection molding under conditions of a molding temperature of 260°C and a mold temperature of 80°C. Each test piece obtained was evaluated according to the evaluation criteria defined in ISO527-1 and 2. The evaluation results are shown in Tables 1 and 2.

[Bending strength and bending elastic modulus]
After drying the obtained pellets at 140 ° C. for 3 hours, injection molding is performed at a molding temperature of 260 ° C. and a mold temperature of 80 ° C. to prepare a bending test piece of 80 mm × 10 mm × 4 mm in accordance with ISO 3167, defined in ISO 178. It was evaluated according to the established evaluation criteria. The evaluation results are shown in Tables 1 and 2.

[Charpy impact strength]
After drying the obtained pellets at 140 ° C. for 3 hours, injection molding was performed at a molding temperature of 260 ° C. and a mold temperature of 80 ° C. to prepare a notched Charpy impact test piece of 80 mm × 10 mm × 4 mm in accordance with ISO 3167. Charpy impact strength (notched) (kJ/m ² ) was measured according to ISO179/1eA.

As is clear from Tables 1 and 2, the insert-molded article made of the resin composition of Example 1 was a reference example regardless of whether the shape of the insert member was a square prism, an L-shaped plate, or an I-shaped plate. The difference from the value of 1 is small, and the decrease in heat shock resistance from the non-colored product (Reference Example 1) is suppressed. Therefore, this insert-molded article can suppress the occurrence of heat shock fracture even when used in an environment with large temperature changes, in spite of containing a coloring agent. Although the insert-molded product made of the resin composition of Comparative Example 1 can suppress the deterioration of the heat shock resistance when using the quadrangular prism-shaped insert member, when using the L-shaped or I-shaped plate-shaped insert member , the heat shock resistance is further reduced. The insert-molded products made of the resin compositions of Comparative Examples 2, 3, and 4 exhibited lower heat shock resistance regardless of whether the shape of the insert member was a square prism or an L-shaped or I-shaped plate. Resulting in.

1, 21, 31 resin member 2, 22, 32 insert member 10, 20, 30 test piece

Claims (12)

having a resin member and an insert member,
The resin member contains a thermoplastic aromatic polyester resin composition containing a thermoplastic aromatic polyester resin A and a coloring agent B having an average primary particle size of 25 nm or more and 50 nm or less,
the insert member is a plate-shaped member containing a metal, an alloy or an inorganic solid,
An insert-molded article, which is an injection-molded article having excellent heat shock resistance, in which the coloring agent B contains carbon black. having a resin member and an insert member,
The resin member contains a thermoplastic aromatic polyester resin composition containing a thermoplastic aromatic polyester resin A and a coloring agent B having an average primary particle size of 25 nm or more and 50 nm or less,
the insert member is a plate-shaped member containing a metal, an alloy or an inorganic solid,
The coloring agent B contains carbon black,
An insert-molded product with excellent heat shock resistance in which the resin member has a welded portion . having a resin member and an insert member,
The resin member contains a thermoplastic aromatic polyester resin composition containing a thermoplastic aromatic polyester resin A and a coloring agent B having an average primary particle size of 25 nm or more and 50 nm or less,
the insert member is a plate-shaped member containing a metal, an alloy or an inorganic solid,
The coloring agent B contains carbon black,
An insert molded article having excellent heat shock resistance , wherein at least a part of an insert member is coated with a resin member, and the thickness of at least a part of the resin member in the coated portion is 0.3 mm or more and 5 mm or less . The insert-molded article according to any one of claims 1 to 3, wherein the content of the colorant B in the thermoplastic aromatic polyester resin composition is 0.05% by mass or more and 5.0% by mass or less. The insert-molded article according to any one of claims 1 to 4, wherein the thermoplastic aromatic polyester resin A contains a polybutylene terephthalate-based resin. The insert-molded article according to any one of claims 1 to 5 , wherein the average primary particle size of the coloring agent B is 27 nm or more and 40 nm or less. The insert member has a main surface having a longitudinal direction and a width direction, and the ratio of the maximum width to the maximum thickness is 2 or more in a cross section taken along a plane perpendicular to the longitudinal direction. The insert molded product according to any one of claims 1 to 6 . The insert molded product according to any one of claims 1 to 7 , wherein the insert member has a thickness of 0.1 mm or more and 3 mm or less. 9. Any one of claims 1 , 2, 4 to 8 , wherein at least a portion of the insert member is coated with a resin member, and the thickness of at least a portion of the resin member in the coated portion is 0.3 mm or more and 5 mm or less. The insert-molded product described in the paragraph. The insert-molded article according to any one of claims 1 to 9, wherein the thermoplastic aromatic polyester resin A is a polybutylene terephthalate-based resin. The insert-molded article according to any one of claims 1 to 10, wherein the thermoplastic aromatic polyester resin composition contains an elastomer. A method for suppressing deterioration of heat shock resistance of a colored insert-molded product, comprising:
An insert-molded product is produced using a plate-like insert member and a resin composition obtained by blending a thermoplastic aromatic polyester resin A with a coloring agent B having an average primary particle size of 25 nm or more and 50 nm or less,
A method wherein colorant B comprises carbon black.

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