Resin composition, pellet, molded article, method for producing resin composition, kit, laser-welded article, and method for producing laser-welded article

Abstract

To provide a novel resin composition which can be used as a laser absorbing resin member during laser welding and can be marked with a laser, and to provide a pellet, a molded article, a method for producing a resin composition, a kit, a laser welded article, and a method for producing a laser welded article.SOLUTION: Disclosed is a resin composition containing 0. 01-0. 4 parts by mass of carbon black with respect to a total of 100 parts by mass of more than 50 parts by mass and 99.9 parts by mass of a polyester resin and 0. 1-50 parts by mass of an amorphous resin, wherein at least part of the amorphous resin is derived from a master batch of the carbon black.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a resin composition, a pellet, a molded article, a method for producing a resin composition, a kit, a laser-welded article, and a method for producing a laser-welded article. In particular, the present invention relates to a resin composition containing a polyester resin as a main component. [Background technology]

[0002] Polyester resins, including polybutylene terephthalate resins, are widely used in various equipment components because they have excellent mechanical strength, chemical resistance, electrical insulation, and other properties, as well as excellent heat resistance, moldability, and recyclability.

[0003] Recently, welding has become more common to improve productivity, and laser welding, which has little impact on electronic components, is becoming increasingly popular. Laser welding is a technique in which a laser-transmitting resin member (hereinafter sometimes referred to as "transmitting resin member") made of a laser-transmitting material is superimposed on a laser-absorbing resin member (hereinafter sometimes referred to as "absorbing resin member") made of a laser-absorbent material, and laser light is irradiated from the transmitting resin member side to heat the interface with the absorbing resin member and weld them together. Resin compositions used in molded products for such purposes are required to have the ability to be welded by irradiation with laser light (laser weldability).

[0004] On the other hand, in the case of molded products, product information is often printed or drawn on the surface of the molded product for the purpose of designing the finished product, displaying information, and identifiable parts during assembly. When it is required that the visibility of the markings be maintained for a long period of time, laser marking is sometimes used from the viewpoint of reliability. Furthermore, in recent years, resin compositions that can be used as laser-absorbing resin members during laser welding and that are laser-markable have also been investigated (Patent Document 1). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2020-050822 Summary of the Invention [Problem to be solved by the invention]

[0006] As described above, resin compositions that can be used as laser-absorbing resin members during laser welding and that are laser-markable have been studied, but as demand for resin compositions with such properties increases, new resin compositions are needed. The present invention aims to solve these problems, and to provide a novel resin composition that can be used as a laser-absorbing resin part during laser welding and that is laser-markable, as well as pellets, molded products, methods for producing resin compositions, kits, laser-welded products, and methods for producing laser-welded products. [Means for solving the problem]

[0007] In light of the above-mentioned problems, the present inventors have conducted research and found that the above-mentioned problems can be solved by blending a masterbatch of carbon black with a predetermined resin in addition to a polyester resin. Specifically, the above problems were solved by the following means. <1> A resin composition comprising: more than 50 parts by mass but not more than 99.9 parts by mass of polyester resin; and 0.1 part by mass or more but not more than 50 parts by mass of amorphous resin, for a total of 100 parts by mass, and 0.01 part by mass or more but not more than 0.4 parts by mass of carbon black; and at least a portion of the amorphous resin is derived from a masterbatch of the carbon black. <2> The polyester resin includes a polybutylene terephthalate resin. <1> The resin composition according to claim 1. <3> The SP value of the polyester resin (SP 1 ) and the SP value of the amorphous resin (SP 2) absolute value of the difference (|SP 1 -SP 2 |) is between 0 and 3.0, <1> or <2> The resin composition according to claim 1. <4> The amorphous resin includes a styrene-based resin. <1> ~ <3> The resin composition according to any one of the above. <5> The amorphous resin includes an acrylonitrile-styrene resin. <1> ~ <4> The resin composition according to any one of the above. <6> Further, the present invention includes an elastomer. <1> ~ <5> The resin composition according to any one of the above. <7> Used on the laser light absorbing side during laser welding, <1> ~ <6> The resin composition according to any one of the above. <8> Used on the laser light absorbing side during laser welding and for laser marking. <1> ~ <7> The resin composition according to any one of the above. <9> The polyester resin contains a polybutylene terephthalate resin, the amorphous resin contains an acrylonitrile-styrene resin, and further contains an elastomer, the adhesive is used on the laser light absorbing side during laser welding, and is for laser marking. <1> ~ <8> The resin composition according to any one of the above. <10> The polyester resin contains 0.01 parts by mass or more and 0.4 parts by mass or less of carbon black relative to 100 parts by mass of a total of a polyester resin and a second thermoplastic resin other than the polyester resin, and at least a part of the second thermoplastic resin is derived from a master batch of the carbon black, and the SP value of the polyester resin (SP 1 ) and the SP value of the second thermoplastic resin (SP 22 ) absolute value of the difference (|SP 1 -SP 22 |) is 0 to 3.0. <11> The polyester resin contains polybutylene terephthalate resin, is used on the laser light absorbing side during laser welding, and is for laser marking. <10> The resin composition according to claim 1. <12> <1> ~ <11> A pellet of the resin composition according to any one of the above. <13> <1> ~ <11> A molded article formed from the resin composition according to any one of the above items. <14> A method for producing a resin composition, comprising adding and melt-kneading 0.01 part by mass or more and 0.4 part by mass or less of carbon black to a total of 100 parts by mass of more than 50 parts by mass but not more than 99.9 parts by mass of a polyester resin and 0.1 part by mass or more and 50 parts by mass or less of an amorphous resin, wherein at least a portion of the amorphous resin is added as a masterbatch of the carbon black. <15> The resin composition <1> ~ <11> The resin composition according to any one of the above items. <14> The manufacturing method described in <16> a laser-transmittable resin composition; <1> ~ <11> A kit comprising the resin composition according to any one of the above. <17> a laser-transmittable resin member formed from a laser-transmittable resin composition; <1> ~ <11> 2. A laser-welded article formed from the resin composition according to any one of claims 1 to 11 and a laser-absorbing resin member. <18> The method includes irradiating a laser with a laser to laser-mark a laser-absorbing resin member, and laser welding the laser-transmitting resin member and the laser-absorbing resin member. <17> A method for producing a laser welded product according to claim 1. <19> The laser welding is performed by galvano scanning laser welding. <18> A method for producing a laser welded product according to claim 1. [Effects of the Invention]

[0008] It is now possible to provide a new resin composition that can be used as a laser-absorbing resin member during laser welding and that is laser-markable, as well as pellets, molded products, a method for producing the resin composition, a kit, a laser-welded product, and a method for producing a laser-welded product. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 2 is a schematic view showing a test piece (transmissive resin member I) for measuring the laser welding strength of the examples. [Figure 2]FIG. 2 is a schematic diagram showing a test piece (absorbent resin member II) for measuring the laser welding strength of the examples. [Figure 3] FIG. 2 is a schematic diagram showing a test piece (a combination of a transmissive resin member I and an absorptive resin member II) for measuring the laser welding strength of the examples. [Figure 4] FIG. 2 is a schematic diagram showing a method for measuring laser welding strength in the examples. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, an embodiment for carrying out the present invention (hereinafter simply referred to as "the present embodiment") will be described in detail. Note that the present embodiment is an example for explaining the present invention, and the present invention is not limited to only this embodiment. In this specification, the symbol "to" is used to mean that the numerical values ​​before and after it are included as the lower limit and upper limit. In this specification, various physical properties and characteristic values ​​are those at 23°C unless otherwise specified. In this specification, unless otherwise specified, the weight average molecular weight is a polystyrene-equivalent value measured by GPC (gel permeation chromatography) using a Tosoh HLC-8320GPC EcoSEC column, tetrahydrofuran as a solvent, and Shodex KF-G, KF-805L x 3, KF-800D columns at a column temperature of 40°C and a flow rate of 1.2 mL / min, detected at a detection wavelength of 254 nm. If the measurement methods, etc. described in the standards shown in this specification differ from year to year, they will be based on the standards in effect as of January 1, 2023, unless otherwise stated. The scale of Figures 1 to 4 may not be consistent with reality.

[0011] The resin composition of this embodiment is characterized in that it contains 0.01 to 0.4 parts by mass of carbon black per 100 parts by mass of a total of more than 50 to 99.9 parts by mass of polyester resin (preferably more than 50 to 90 parts by mass) and 0.1 to 50 parts by mass of amorphous resin (preferably 10 to 50 parts by mass), and at least a portion of the amorphous resin is derived from a masterbatch of the carbon black. This configuration makes it possible to provide a resin composition that can be used as a laser-absorbing resin member during laser welding and that is laser-markable. Here, "at least a portion of the amorphous resin is derived from the carbon black masterbatch" means that at least a portion of the amorphous resin is used as a resin for the carbon black masterbatch and is a component added to the resin composition.

[0012] In this embodiment, in addition to the polyester resin, an amorphous resin is included, and the carbon black is added in a masterbatch state with the amorphous resin. It is believed that this configuration creates islands of amorphous resin in a sea of ​​polyester resin in the resin composition, and that the carbon black tends to aggregate within the islands. It is believed that this results in concentrated heat generation by the aggregated carbon black, thereby increasing the laser welding strength.

[0013] In another embodiment, the polyester resin composition contains 0.01 parts by mass or more and 0.4 parts by mass or less of carbon black relative to a total of 100 parts by mass of more than 50 parts by mass and 99.9 parts by mass or less (preferably more than 50 parts by mass and 90 parts by mass or less) of a polyester resin and 0.1 parts by mass or more and 50 parts by mass or less (preferably 10 parts by mass or more and 50 parts by mass or less) of a second thermoplastic resin other than the polyester resin, and at least a portion of the second thermoplastic resin is derived from a masterbatch of the carbon black, and the SP value of the polyester resin (SP 1 ) and the SP value of the second thermoplastic resin (SP 22 ) absolute value of the difference (|SP 1 -SP 22|) is 0 to 3.0. In this embodiment, the carbon black has a SP value (SP 1 ) and SP value (SP 22 ) absolute value of the difference (|SP 1 -SP 22 The carbon black is added in a state where it has been masterbatched with a second thermoplastic resin having a thermal expansion coefficient (Tc) of 0 to 3.0. By using such a configuration, islands of the second thermoplastic resin are formed in a sea of ​​polyester resin in the resin composition, and it is presumed that the carbon black tends to aggregate easily in the islands. As a result, it is presumed that the aggregated carbon black generates heat in a concentrated manner, thereby increasing the laser welding strength. The details of this embodiment will be described below.

[0014] <Polyester resin> The resin composition of the present embodiment contains a polyester resin. The polyester resin is a polyester obtained by polycondensation of a dicarboxylic acid compound and a dihydroxy compound, polycondensation of an oxycarboxylic acid compound, or polycondensation of these compounds, and may be either a homopolyester or a copolyester. The polyester resin used in this embodiment is preferably a polyalkylene terephthalate resin, more preferably a polyethylene terephthalate resin and / or a polybutylene terephthalate resin, and even more preferably a polybutylene terephthalate resin. The polyester resin used in this embodiment is a crystalline resin.

[0015] As the dicarboxylic acid compound constituting the polyester resin, aromatic dicarboxylic acids or their ester-forming derivatives are preferably used. Examples of aromatic dicarboxylic acids include terephthalic acid, isophthalic acid, orthophthalic acid, 1,5-naphthalenedicarboxylic acid, 2,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, biphenyl-2,2'-dicarboxylic acid, biphenyl-3,3'-dicarboxylic acid, biphenyl-4,4'-dicarboxylic acid, diphenylether-4,4'-dicarboxylic acid, diphenylmethane-4,4'-dicarboxylic acid, diphenylsulfone-4,4'-dicarboxylic acid, diphenylisopropylidene-4,4'-dicarboxylic acid, 1,2-bis(phenoxy)ethane-4,4'-dicarboxylic acid, anthracene-2,5-dicarboxylic acid, anthracene-2,6-dicarboxylic acid, p-tert-phenylene-4,4'-dicarboxylic acid, and pyridine-2,5-dicarboxylic acid, and terephthalic acid is preferably used.

[0016] These aromatic dicarboxylic acids may be used in combination of two or more kinds. As is well known, these can be used in the polycondensation reaction not only as free acids but also as ester-forming derivatives such as dimethyl esters. In addition, these aromatic dicarboxylic acids can be used in small amounts in combination with one or more aliphatic dicarboxylic acids such as adipic acid, azelaic acid, dodecanedioic acid, and sebacic acid, and alicyclic dicarboxylic acids such as 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, and 1,4-cyclohexanedicarboxylic acid.

[0017] Examples of dihydroxy compounds constituting the polyester resin include aliphatic diols such as ethylene glycol, propylene glycol, butanediol, hexylene glycol, neopentyl glycol, 2-methylpropane-1,3-diol, diethylene glycol, and triethylene glycol, alicyclic diols such as cyclohexane-1,4-dimethanol, and mixtures thereof. In addition, a small amount of one or more long-chain diols having a molecular weight of 400 to 6,000, such as polyethylene glycol, poly-1,3-propylene glycol, and polytetramethylene glycol, may be copolymerized. Additionally, aromatic diols such as hydroquinone, resorcinol, naphthalenediol, dihydroxydiphenyl ether, and 2,2-bis(4-hydroxyphenyl)propane can also be used.

[0018] In addition to the above-mentioned bifunctional monomers, a small amount of a trifunctional monomer such as trimellitic acid, trimesic acid, pyromellitic acid, pentaerythritol, or trimethylolpropane can be used in combination to introduce a branched structure, or a monofunctional compound such as a fatty acid can be used in combination to adjust the molecular weight. The polyester resin is usually formed by polycondensation of a dicarboxylic acid and a diol, i.e., 50% by mass, preferably 70% by mass or more of the total polyester resin is formed by this polycondensation product. The dicarboxylic acid is preferably an aromatic carboxylic acid, and the diol is preferably an aliphatic diol.

[0019] Among these, polyalkylene terephthalate resins in which 95 mol % or more of the acid component is terephthalic acid and 95 mass % or more of the alcohol component is an aliphatic diol are preferred. Representative examples include polybutylene terephthalate resin and polyethylene terephthalate resin, with polybutylene terephthalate resin being preferred. These are preferably similar to homopolyesters, i.e., 95 mass % or more of the resin as a whole is preferably composed of terephthalic acid and 1,4-butanediol or ethylene glycol.

[0020] The polyester resin is also preferably copolymerized with isophthalic acid, dimer acid, polytetramethylene glycol (PTMG), or other polyalkylene glycol, and more preferably isophthalic acid. Examples of these copolymers include those in which the copolymerization amount is 1 mol % or more but less than 50 mol %, preferably less than 40 mol %, more preferably less than 30 mol %, and even less than 20 mol %, of the total polyalkylene terephthalate segments.

[0021] The polyester resin used in this embodiment may contain recycled products. Examples of recycled polyester resins include those obtained by material recycling, in which scraps or rejected products from molded products, or recovered used polyester resin molded bodies are crushed, washed, and reused, and those obtained by chemical recycling (chemical decomposition method).

[0022] An example of a blend form of the polyester resin of this embodiment is one in which at least a polybutylene terephthalate resin is included. The mass ratio of the polybutylene terephthalate resin in this blend form is preferably 30% by mass or more, more preferably 50% by mass or more, even more preferably 52% by mass or more, even more preferably 70% by mass or more, even more preferably 80% by mass or more, even more preferably 90% by mass or more, and may even be 95% by mass or more, based on 100% by mass of the polyester resin. By adjusting the mass ratio to be equal to or greater than the lower limit, the deflection temperature under load of the resulting molded article tends to be higher, and the moldability of the resin composition tends to be better. The mass ratio of the polybutylene terephthalate resin in the first embodiment may be 100% by mass based on 100% by mass of the polyester resin contained in the resin composition, or may be 90% by mass or less, 70% by mass or less, or 60% by mass or less, depending on the intended use.

[0023] The polybutylene terephthalate resin used in this embodiment may be a homopolymer of polybutylene terephthalate, or a copolymer partially containing isophthalic acid, dimer acid, or a polyalkylene glycol such as polytetramethylene glycol (PTMG). Preferably, 1 to 30 mol % (preferably 5 to 25 mol %) of the terephthalic acid component in the polybutylene terephthalate resin may be modified with isophthalic acid. Use of such an isophthalic acid-modified polybutylene terephthalate resin tends to further improve toughness, fluidity, tracking resistance, and laser welding strength.

[0024] In the above blend form, the resin other than the polybutylene terephthalate resin is preferably a polyethylene terephthalate resin. In the above blend form, it is particularly preferred that the polybutylene terephthalate resin is contained in an amount of 30% by mass or more (preferably 50% by mass or more) relative to 100% by mass of the polyester resin, and the total of the polybutylene terephthalate resin and the polyethylene terephthalate resin (the content of the polyethylene terephthalate resin may be 0% by mass) accounts for 90% by mass or more (preferably 95% by mass or more) relative to 100% by mass of the polyester resin. By blending the polyethylene terephthalate resin, warpage of the resulting molded article tends to be more effectively suppressed.

[0025] The SP value of the polyester resin used in this embodiment is preferably 18.5 or more, more preferably 19.0 or more, and even more preferably 20.0 or more, and is preferably 23.0 or less, more preferably 22.0 or less, and may be 21.5 or less. The SP value can be calculated by determining the solubility in a solvent with a known SP value and using the Hansen Solubility Parameters in Practice ver. 5.0. When the resin composition of the present embodiment contains two or more polyester resins, the SP value is the sum of the values ​​obtained by multiplying the SP value of each polyester resin by the mass fraction.

[0026] The terminal carboxyl group concentration of the polyester resin is preferably 1 to 23 eq / ton, and more preferably 7 to 22 eq / ton. By setting the concentration in this range, the flowability of the resin composition tends to be further improved. In the case where the resin composition of the present embodiment contains two or more polyester resins, the terminal carboxyl group concentration of the polyester resin is the terminal carboxyl group concentration of the mixture. The amount of terminal carboxyl groups can be determined by dissolving 0.5 g of polyester resin in 25 mL of benzyl alcohol and titrating the resultant solution with a 0.01 mol / L benzyl alcohol solution of sodium hydroxide.

[0027] The polyester resin used in this embodiment preferably has an intrinsic viscosity of 0.40 to 2.00 dL / g. By setting the intrinsic viscosity to the upper limit or less, the moldability of the resulting molded article tends to be further improved. Furthermore, by setting the intrinsic viscosity to the lower limit or more, the mechanical properties such as tensile strength and flexural strength tend to be further improved. The intrinsic viscosity of the polyester resin is preferably 0.50 dL / g or more, more preferably 0.65 dL / g or more, and even more preferably 0.70 dL / g or more, and is preferably 1.50 dL / g or less, and more preferably 1.00 dL / g or less.

[0028] The intrinsic viscosity of the polyester resin is measured by the following method. Polybutylene terephthalate resin pellets are dissolved in a mixed solvent of phenol / 1,1,2,2-tetrachloroethane (1 / 1 by mass) by stirring at 110°C for 1 hour to a concentration of 1.00 g / dL. The solution is then cooled to 30°C. Using a fully automatic solution viscometer, the time it takes for the sample solution and the solvent alone to fall is measured at 30°C, and the intrinsic viscosity is calculated using the formula: Intrinsic viscosity=((1+4K H η sp ) 0.5 -1) / (2K H C) where η sp =η / η0-1, where η is the time it takes for the sample solution to fall, η0 is the time it takes for the solvent alone to fall, C is the concentration of the sample solution (g / dL), and K H is Huggins' constant. K H was set to 0.33. In the case where the resin composition of the present embodiment contains two or more polyester resins, the intrinsic viscosity of the polyester resin is the intrinsic viscosity of the mixture.

[0029] The resin composition in this embodiment preferably contains polyester resin in a proportion of 20% by mass or more, more preferably 25% by mass or more, even more preferably 30% by mass or more, and even more preferably 42% by mass or more, based on 100% by mass of the resin composition, and preferably contains polyester resin in a proportion of 95% by mass or less, more preferably 90% by mass or less, even more preferably 70% by mass or less, preferably 55% by mass or less, more preferably 50% by mass or less, and even more preferably 45% by mass or less. The resin composition in the present embodiment may contain only one type of polyester resin, or may contain two or more types. When two or more types are contained, the total amount is preferably in the above range.

[0030] <Amorphous resin and / or second thermoplastic resin> The resin composition of this embodiment contains an amorphous resin and / or a second thermoplastic resin. It is presumed that the inclusion of these resins causes the amorphous resin and / or the second thermoplastic resin to form a sea-island structure in the resin composition, making it easier for the carbon black to aggregate in the island portions, and the aggregated carbon black generates heat in a concentrated manner, thereby increasing the laser welding strength. The resin composition of the present embodiment may be in a form containing both an amorphous resin and / or a second thermoplastic resin derived from the carbon black masterbatch, and an amorphous resin and / or a second thermoplastic resin blended separately from the masterbatch. However, in order to achieve low warpage of the thermoplastic resin, it is preferable that the resin composition contains an amorphous resin blended separately from the masterbatch. The amorphous resin and / or second thermoplastic resin derived from the carbon black masterbatch and the amorphous resin and / or second thermoplastic resin blended separately from the masterbatch may be the same resin or different resins. In this embodiment, it is also preferable that the amorphous resin and / or second thermoplastic resin derived from the carbon black masterbatch and the amorphous resin and / or second thermoplastic resin blended separately from the masterbatch each contain a styrene-based resin. Details of these resins will be described later.

[0031] In a first example of this embodiment, the amount of the amorphous resin and / or the second thermoplastic resin derived from the carbon black masterbatch is preferably 0.05% by mass or more, more preferably 0.1% by mass or more, and is preferably 10% by mass or less, more preferably 5% by mass or less, based on a total amount (100% by mass) of the amorphous resin and / or the second thermoplastic resin contained in the resin composition. In a second example of this embodiment, the amount of the amorphous resin and / or the second thermoplastic resin derived from the carbon black masterbatch is preferably more than 90 mass%, more preferably more than 95 mass%, and may be 100 mass% or less, based on 100 mass% of the total amount of the amorphous resin and / or the second thermoplastic resin contained in the resin composition. By adopting such a configuration, the laser weldability of the resulting molded article can be further improved.

[0032] In one embodiment of the present invention, the SP value of the polyester resin (SP 1 ) and the SP value of amorphous resin (SP 2 ) Absolute value of the difference |SP 1 -SP 2 | is between 0 and 3.0. In another aspect of the present embodiment, the SP value of the polyester resin (SP 1 ) and the SP value of the second thermoplastic resin (SP 22 ) Absolute value of the difference |SP 1 -SP 22 | is between 0 and 3.0. In this embodiment, the absolute value of the difference between the SP values ​​(|SP 1 -SP 2 |, |SP 1 -SP 22 |) is preferably greater than 0, more preferably 0.1 or greater, even more preferably 0.5 or greater, even more preferably 1.0 or greater, even more preferably 1.5 or greater, even more preferably 2.0 or greater, and preferably 2.8 or less. In this embodiment, the SP value of the polyester resin (SP 1 ) ≧ SP value of amorphous resin (SP 2 ) is preferred. When the resin composition of the present embodiment contains two or more types of amorphous resins and / or second thermoplastic resins, the SP value is the sum of the values ​​obtained by multiplying the SP value of each polyester resin by the mass fraction.

[0033] In this embodiment, the SP value of the amorphous resin (SP 2 ) and / or the SP value of the second thermoplastic resin (SP 22 ) are each independently preferably 21.5 or less, more preferably 21.0 or less, even more preferably less than 20.0, more preferably 19.5 or less, even more preferably less than 19.0, and may be less than 18.5, and are preferably 17.0 or more, and may be 17.5 or more.

[0034] Examples of the amorphous resin include a styrene-based resin, a polycarbonate resin, a polyphenylene ether resin, and a polysulfone resin, and the styrene-based resin and the polycarbonate resin are preferred, and the styrene-based resin is more preferred. In the resin composition used in this embodiment, it is preferred that 90 mass % or more of the amorphous resin is a styrene-based resin.

[0035] <<Styrene-based resin>> Examples of styrene-based resins include resins obtained by polymerizing styrene-based monomers and, if necessary, one or more other vinyl monomers copolymerizable therewith.

[0036] Examples of the styrene-based monomer include styrene, α-methylstyrene, o-methylstyrene, p-methylstyrene, vinylxylene, ethylstyrene, dimethylstyrene, p-tert-butylstyrene, vinylnaphthalene, and other styrene derivatives, with styrene being particularly preferred. These may be used alone or in combination of two or more.

[0037] Other vinyl monomers copolymerizable with styrene-based monomers include α,β-unsaturated carboxylic acids and their anhydrides, such as acrylic acid, methacrylic acid, maleic acid, maleic anhydride, phthalic acid, and itaconic acid; methacrylic acid alkyl esters, such as methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, amyl methacrylate, hexyl methacrylate, 2-ethylhexyl methacrylate, octyl methacrylate, cyclohexyl methacrylate, and dodecyl methacrylate; methyl acrylate, ethyl acrylate, and the like. Examples of the acrylic acid ester include alkyl esters of acrylic acid such as butyl acrylate, propyl acrylate, butyl acrylate, amyl acrylate, hexyl acrylate, 2-ethylhexyl acrylate, octyl acrylate, cyclohexyl acrylate, and dodecyl acrylate; aryl esters of acrylic acid such as phenyl acrylate and benzyl acrylate; aryl methacrylate esters such as phenyl methacrylate and benzyl methacrylate; maleimide-based monomers such as maleimide, N-methylmaleimide, and N-phenylmaleimide; and acrylonitrile.

[0038] As the styrene-based resin, from the viewpoint of low warpage and basic physical properties, a copolymer of a styrene-based monomer and an acrylonitrile monomer (acrylonitrile-styrene resin) is preferred. In the acrylonitrile-styrene resin, the proportion of styrene-based monomers in the total of 100% by mass of the monomers constituting the resin is preferably 20% by mass or more, more preferably 30% by mass or more, and is preferably 90% by mass or less, more preferably 80% by mass or less, and even more preferably 70% by mass or less. The acrylonitrile-styrene resin may be a copolymer of a styrene-based monomer, acrylonitrile, and another monomer copolymerizable with either of them. The proportion of the other monomer is preferably 30% by mass or less, more preferably 20% by mass or less, even more preferably 10% by mass or less, particularly preferably 5% by mass or less, 3% by mass or less, 2% by mass or less, and particularly preferably 1% by mass or less, based on 100% by mass of the total monomers constituting the acrylonitrile-styrene resin. There are no limitations on the method for producing the acrylonitrile-styrene resin, and known methods can be used, such as bulk polymerization, emulsion polymerization, solution polymerization, and suspension polymerization.

[0039] <<Polycarbonate resin>> The polycarbonate resin used in this embodiment may be a known polycarbonate resin. Polycarbonate resins are generally thermoplastic polymers or copolymers, which may be branched, obtained by reacting a dihydroxy compound or a small amount of a polyhydroxy compound with phosgene or a carbonate diester. The method for producing the polycarbonate resin is not particularly limited, and polycarbonate resins produced by the conventionally known phosgene method (interfacial polymerization method) or melt method (ester exchange method) may be used. However, polycarbonate resins produced by the melt method are preferred in terms of laser transparency and laser weldability.

[0040] The dihydroxy compound used as the raw material is preferably an aromatic dihydroxy compound, and examples thereof include 2,2-bis(4-hydroxyphenyl)propane (i.e., bisphenol A), tetramethylbisphenol A, bis(4-hydroxyphenyl)-p-diisopropylbenzene, hydroquinone, resorcinol, and 4,4-dihydroxydiphenyl, with bisphenol A being preferred. Also usable are compounds in which one or more tetraalkylphosphonium sulfonates are bonded to the above aromatic dihydroxy compounds.

[0041] Among the polycarbonate resins mentioned above, aromatic polycarbonate resins derived from 2,2-bis(4-hydroxyphenyl)propane or aromatic polycarbonate copolymers derived from 2,2-bis(4-hydroxyphenyl)propane and other aromatic dihydroxy compounds are preferred. They may also be copolymers, such as copolymers with polymers or oligomers having a siloxane structure. Furthermore, two or more of the above polycarbonate resins may be mixed and used.

[0042] The viscosity-average molecular weight of the polycarbonate resin is preferably 5,000 to 30,000, more preferably 10,000 to 28,000, and even more preferably 14,000 to 24,000. Using a resin with a viscosity-average molecular weight of 5,000 or more tends to improve the mechanical strength of the resulting molded article. Using a resin with a viscosity-average molecular weight of 30,000 or less tends to improve the fluidity of the resin composition, further improving moldability and laser weldability. The viscosity average molecular weight of the polycarbonate resin is the viscosity average molecular weight [Mv] calculated from the solution viscosity measured at 25°C using methylene chloride as a solvent.

[0043] On the other hand, the second thermoplastic resin in this embodiment is a thermoplastic resin other than polyester resin, and the SP value (SP 1 ) and the like. Suitable examples of the second thermoplastic resin are the same as the examples of the amorphous resin described above.

[0044] In this embodiment, when the polyester resin is polybutylene terephthalate resin, examples of the amorphous resin and / or the second thermoplastic resin include styrene-based resin, polycarbonate resin, polyphenylene ether resin, and polysulfone resin (PSF resin). When the polyester resin is polyethylene terephthalate resin, examples of the amorphous resin and / or the second thermoplastic resin include styrene-based resin, polycarbonate resin, etc.

[0045] In this embodiment, the total content of the amorphous resin and / or second thermoplastic resin is 0.1 parts by mass or more, preferably 1 part by mass or more, more preferably 5 parts by mass or more, even more preferably 10 parts by mass or more, even more preferably 15 parts by mass or more, even more preferably 20 parts by mass or more, even more preferably 23 parts by mass or more, and may be 30 parts by mass or more, relative to 100 parts by mass of the total of the polyester resin, the amorphous resin, and / or the second thermoplastic resin. By setting the content at or above the lower limit, warping of the resin composition tends to be reduced. Furthermore, in this embodiment, the total content of the amorphous resin and / or second thermoplastic resin is 50 parts by mass or less, preferably 45 parts by mass or less, more preferably 40 parts by mass or less, even more preferably 38 parts by mass or less, and may be 32 parts by mass or less, or may be less than 10 parts by mass, relative to 100 parts by mass of the total of the polyester resin, the amorphous resin, and / or the second thermoplastic resin. By adjusting the content to the upper limit or less, the heat resistance, mechanical properties such as tensile strength and flexural strength, and laser weldability of the resin composition tend to be further improved.

[0046] <Carbon black> The resin composition of the present embodiment contains carbon black, which enables laser welding and laser marking. In this embodiment, the carbon black is added in a state of being masterbatched with the amorphous resin. Alternatively, the carbon black is added in a state where the SP value (SP 1 ) and SP value (SP 22 ) Absolute value of the difference |SP 1 -SP 22The carbon black is added in a state of being masterbatched with a second thermoplastic resin having a | of 0 to 3.0, preferably 1.0 to 3.0, and more preferably 2.0 to 3.0. By configuring in this way, a sea-island structure is formed in the resin composition by the polyester resin and the amorphous resin, etc., and it is presumed that the carbon black tends to aggregate in the island portions, and the aggregated carbon black concentrates to generate heat, thereby increasing the laser welding strength. Furthermore, the resin composition of the present embodiment may contain both carbon black masterbatched with an amorphous resin and carbon black masterbatched with a second thermoplastic resin that satisfies the absolute value of the difference in SP value described above.

[0047] In this embodiment, the proportion of carbon black in the carbon black masterbatch is preferably 10% by mass or more, more preferably 15% by mass or more, even more preferably 20% by mass or more, even more preferably 25% by mass or more, even more preferably 30% by mass or more, even more preferably 35% by mass or more, and may even be 40% by mass or more or 45% by mass or more, and is preferably 65% ​​by mass or less, more preferably 60% by mass or less, and even more preferably 55% by mass or less. In the carbon black masterbatch used in this embodiment, the total amount of the carbon black, the amorphous resin and / or the second thermoplastic resin preferably accounts for 99 to 100% by mass of the entire carbon black masterbatch.

[0048] The carbon black is not limited in type, raw material, or production method, and any of furnace black, channel black, acetylene black, ketjen black, etc. can be used. Of these, furnace black is preferred. The number-average particle size of carbon black is preferably 5 to 60 nm. The upper limit is preferably 60 nm or less, more preferably 40 nm or less, even more preferably 30 nm or less, and even more preferably 25 nm or less. The lower limit is preferably 10 nm or more, more preferably 13 nm or more, even more preferably 16 nm or more, and even more preferably 19 nm or more. By keeping the size within the above upper and lower limits, the appearance, laser weldability, and laser markability of molded articles tend to be improved. The number-average particle size can be determined by obtaining a magnified image of an aggregate according to the procedure described in ASTM D3849 (Standard Test Method for Carbon Black - Morphological Characterization by Electron Microscopy), measuring the particle sizes of 3,000 unit constituent particles from this aggregate image, and then arithmetically averaging the measured particle sizes.

[0049] DBP oil absorption of carbon black (unit: cm 3 / 100g) is 40~300cm 3 The upper limit is preferably 300 cm / 100 g. 3 / 100g or less is preferable, and 200cm 3 / 100g or less is more preferable, and 150cm 3 / 100g or less is more preferable, and 100cm 3 The lower limit may be 40 cm / 100 g or less. 3 / 100g or more is preferable, 50cm 3 / 100g or more is preferable, 60cm 3 By adjusting the DBP oil absorption amount (unit: cm) to within the above upper and lower limits, the appearance, laser welding strength, and laser marking properties of the molded product tend to be improved. 3 / 100g) can be measured in accordance with JIS K6217.

[0050] The carbon black content in the resin composition of this embodiment is 0.01 parts by mass or more, preferably 0.05 parts by mass or more, more preferably 0.1 parts by mass or more, even more preferably 0.15 parts by mass or more, and even more preferably 0.20 parts by mass or more, per 100 parts by mass of the polyester resin, amorphous resin, and / or second thermoplastic resin combined. By adjusting the carbon black content to be equal to or greater than the lower limit, the coloring effect, laser welding strength, shortened laser welding tact time, and laser marking properties are more effectively exhibited. Furthermore, the upper limit of the carbon black content is 0.4 parts by mass or less, more preferably 0.35 parts by mass or less, per 100 parts by mass of the polyester resin, amorphous resin, and / or second thermoplastic resin combined. By adjusting the carbon black content to be equal to or less than the upper limit, the mechanical strength and laser welding strength of the resulting molded product tend to be further improved.

[0051] The content of the carbon black masterbatch in the resin composition of this embodiment is preferably 0.02 parts by mass or more, more preferably 0.1 parts by mass or more, even more preferably 0.2 parts by mass or more, and even more preferably 0.25 parts by mass or more, per 100 parts by mass of the polyester resin, amorphous resin, and / or second thermoplastic resin combined. By adjusting the content to be equal to or greater than the lower limit, the coloring effect is more effectively exhibited and laser weldability tends to be improved. Furthermore, the upper limit of the carbon black masterbatch content is preferably 1.0 parts by mass or less, more preferably 0.8 parts by mass or less, and even more preferably 0.7 parts by mass or less, per 100 parts by mass of the polyester resin, amorphous resin, and / or second thermoplastic resin combined. By adjusting the content to be equal to or less than the upper limit, the mechanical strength of the resulting molded product tends to be further improved. The resin composition of the present embodiment may contain only one type of carbon black, or may contain two or more types. When two or more types are contained, the total amount is preferably in the above range.

[0052] <Elastomer> The resin composition of this embodiment may contain an elastomer. By containing an elastomer, the impact resistance of the resulting absorbent resin member can be improved. However, the elastomer has rubber properties at room temperature (e.g., 23°C) and does not fall under the category of the amorphous resin and / or the second thermoplastic resin. Specifically, having rubber properties at room temperature means that the flexural modulus at room temperature is 300 MPa or less. As the elastomer, a wide variety of elastomers that are used to improve impact resistance by being blended with polyester resins can be used.

[0053] An example of the elastomer is an elastomer containing an epoxy group. By including an elastomer containing an epoxy group, it is possible to obtain an absorbing resin member having higher impact resistance.

[0054] A first embodiment of the epoxy group-containing elastomer is a copolymer obtained by copolymerizing an α-olefin, a glycidyl ester of an α,β-unsaturated acid, and, if necessary, an unsaturated monomer copolymerizable therewith. It is preferable to use 60 mass % or more of the α-olefin and the glycidyl ester of an α,β-unsaturated acid among all the copolymerization components.

[0055] Examples of α-olefins include ethylene, propylene, butene-1, and pentene-1. Two or more of these may be used. Examples of glycidyl esters of α,β-unsaturated acids include glycidyl acrylate, glycidyl methacrylate, glycidyl ethacrylate, and glycidyl itaconate. Two or more of these may be used. Examples of vinyl monomers copolymerizable with the above components include vinyl ethers, vinyl esters such as vinyl acetate and vinyl propionate, acrylic and methacrylic esters such as methyl, ethyl, propyl, and butyl, acrylonitrile, and styrene. Two or more of these may be used.

[0056] Preferred examples of the epoxy group-containing elastomer of the first embodiment include ethylene / glycidyl methacrylate copolymer, ethylene / glycidyl methacrylate / vinyl acetate copolymer, ethylene / glycidyl methacrylate / alkyl acrylate copolymer, and ethylene / alkyl acrylate / vinyl acetate copolymer. In particular, from the viewpoint of excellent toughness and further improving the moist heat resistance and impact resistance of the absorbent resin member, ethylene / glycidyl methacrylate / alkyl acrylate (preferably butyl acrylate) copolymer is preferred. Specific examples of the epoxy group-containing elastomer of the first embodiment are available under the trade names "Rotadar" (registered trademark) AX8900 and AX8700 manufactured by SK Functional Polymer.

[0057] A second embodiment of the epoxy group-containing elastomer is a core-shell elastomer. The use of a core-shell elastomer facilitates dispersion in polybutylene terephthalate resin due to its small molecular size, and the reaction of reactive groups tends to increase welding strength. An example of a core-shell elastomer is one in which a monomer component is graft-copolymerized onto a core polymer. The core is preferably a rubbery polymer, and examples thereof include acrylonitrile-acrylic rubbery polymer-styrene graft copolymer (ASA resin), methyl methacrylate-acrylic rubbery polymer-styrene graft copolymer (MSA resin), methyl methacrylate-acrylonitrile-acrylic rubbery polymer-styrene graft copolymer (MASA resin), polyorganosiloxane-containing rubbery polymer, etc., with polyorganosiloxane-containing rubbery polymer being preferred. The polyorganosiloxane-containing rubbery polymer usually has a glass transition temperature of 0° C. or lower, preferably −20° C. or lower, and more preferably −30° C. or lower. Specific examples of the rubber component are not particularly limited as long as it contains polyorganosiloxane rubber, and examples thereof include polyorganosiloxane rubber, and composite rubber (IPN type) of polyorganosiloxane rubber and polyalkyl acrylate rubber.

[0058] Specific examples of the monomer component graft-copolymerizable with the core include aromatic vinyl compounds, vinyl cyanide compounds, (meth)acrylic acid ester compounds, (meth)acrylic acid compounds, epoxy group-containing (meth)acrylic acid ester compounds such as glycidyl (meth)acrylate, maleimide compounds such as maleimide, N-methylmaleimide, and N-phenylmaleimide; α,β-unsaturated carboxylic acid compounds such as maleic acid, phthalic acid, and itaconic acid, and anhydrides thereof (for example, maleic anhydride, etc.).

[0059] Specific examples of rubber polymers, aromatic vinyl compounds, vinyl cyanide compounds, and (meth)acrylic acid ester compounds can be found in paragraphs 0042 to 0046 of JP 2019-059813 A, the contents of which are incorporated herein by reference.

[0060] The epoxy group-containing elastomer of the second embodiment is preferably a compound obtained by graft polymerizing an epoxy group-containing (meth)acrylic acid ester compound onto a polyorganosiloxane-containing rubbery polymer (preferably a composite rubber of polyorganosiloxane rubber and polyalkyl acrylate rubber).

[0061] Specific examples of the elastomer containing an epoxy group according to the second embodiment include "Metablen (registered trademark, the same applies hereinafter) S-2002" and "Metablen S-2200" manufactured by Mitsubishi Rayon Co., Ltd.

[0062] Another example of the elastomer is a graft copolymer obtained by graft copolymerizing a rubber component with a monomer component copolymerizable therewith. The graft copolymer may be produced by any of bulk polymerization, solution polymerization, suspension polymerization, emulsion polymerization, etc., and the copolymerization method may be either single-stage grafting or multi-stage grafting.

[0063] The rubber component typically has a glass transition temperature of 0°C or lower, preferably -20°C or lower, and more preferably -30°C or lower. Specific examples of the rubber component include polybutadiene rubber, polyisoprene rubber, polyalkyl acrylate rubbers such as polybutyl acrylate, poly(2-ethylhexyl acrylate), and butyl acrylate-2-ethylhexyl acrylate copolymers, silicone rubbers such as polyorganosiloxane rubber, butadiene-acrylic composite rubber, IPN (Interpenetrating Polymer Network) composite rubbers consisting of polyorganosiloxane rubber and polyalkyl acrylate rubber, styrene-butadiene rubber, ethylene-α-olefin rubbers such as ethylene-propylene rubber, ethylene-butene rubber, and ethylene-octene rubber, ethylene-acrylic rubber, and fluororubber. These may be used alone or in combination. Among these, polybutadiene rubber, polyalkyl acrylate rubber, polyorganosiloxane rubber, IPN type composite rubber consisting of polyorganosiloxane rubber and polyalkyl acrylate rubber, styrene-butadiene rubber, and ethylene-acrylic rubber are preferred in terms of mechanical properties and surface appearance.

[0064] Specific examples of the monomer component capable of graft copolymerization with the rubber component are the same as the specific examples of the monomer component capable of graft copolymerization with the rubber component described in the second embodiment of the elastomer containing an epoxy group.

[0065] The graft copolymer obtained by copolymerizing a rubber component is preferably a core / shell graft copolymer in terms of impact resistance and surface appearance. Among these, a core / shell graft copolymer is particularly preferred, which comprises a core layer made of at least one rubber component selected from polybutadiene-containing rubber, polybutyl acrylate-containing rubber, polyorganosiloxane rubber, and an IPN-type composite rubber composed of polyorganosiloxane rubber and polyalkyl acrylate rubber, and a shell layer formed by copolymerizing a (meth)acrylic acid ester around the core layer. The core / shell graft copolymer preferably contains 40% by mass or more of the rubber component, more preferably 60% by mass or more. Furthermore, it is preferable that the (meth)acrylic acid content be 10% by mass or more. Note that the core / shell type in this embodiment does not necessarily have to be one in which the core layer and the shell layer are clearly distinguishable; it broadly includes compounds obtained by graft polymerizing a rubber component around the core portion.

[0066] Preferred specific examples of these core / shell type graft copolymers include methyl methacrylate-butadiene-styrene copolymer (MBS), methyl methacrylate-acrylonitrile-butadiene-styrene copolymer (MABS), methyl methacrylate-butadiene copolymer (MB), methyl methacrylate-acrylic rubber copolymer (MA), methyl methacrylate-acrylic rubber-styrene copolymer (MAS), methyl methacrylate-acrylic-butadiene rubber copolymer, methyl methacrylate-acrylic-butadiene rubber-styrene copolymer, methyl methacrylate-(acrylic-silicone IPN rubber) copolymer, etc. Such rubbery polymers may be used alone or in combination of two or more.

[0067] Examples of such elastomers include Paraloid (registered trademark, the same applies hereinafter) EXL2602, Paraloid (registered trademark, the same applies hereinafter) EXL2603, Paraloid (registered trademark, the same applies hereinafter) EXL2655, Paraloid (registered trademark, the same applies hereinafter) EXL2311, Paraloid (registered trademark, the same applies hereinafter) EXL2313, Paraloid (registered trademark, the same applies hereinafter) EXL2315, Paraloid (registered trademark, the same applies hereinafter) KM330, Paraloid (registered trademark, the same applies hereinafter) KM336P, Paraloid (registered trademark, the same applies hereinafter) KCZ201, Metablen (registered trademark, the same applies hereinafter) C-223A, Metablen (registered trademark, the same applies hereinafter) E-901, Metablen (registered trademark, the same applies hereinafter) S-2001, Metablen (registered trademark, the same applies hereinafter) SRK-200, Kaneka Corporation, Kane Ace (registered trademark, the same applies hereinafter) M-511, Kane Ace M-600, Kane Ace M-400, Kane Ace M-580, Kane Ace M-711, Kane Ace MR-01, Kane Ace M-580, Kane Ace M-711, Kane Ace MR-01, Ube Industries, Ltd., and UBESTA XPA.

[0068] The elastomer (especially an epoxy group-containing elastomer) preferably has a melt flow rate (MFR) of 0.1 to 50 g / 10 min, more preferably 0.5 to 30 g / 10 min, measured at 190°C under a load of 2.16 kgf according to JIS K 7210. By setting the MFR within the above range, there is a tendency for impact resistance to be improved while appearance defects are more effectively suppressed.

[0069] When the resin composition of this embodiment contains an elastomer, the content thereof is preferably 0.1 parts by mass or more, more preferably 1 part by mass or more, even more preferably 5 parts by mass or more, even more preferably 7 parts by mass or more, and even more preferably 9 parts by mass or more, relative to 100 parts by mass of the polyester resin, amorphous resin, and / or second thermoplastic resin combined. By ensuring that the content is equal to or greater than the lower limit, impact resistance and laser weld strength tend to be improved. Furthermore, the content of the elastomer is preferably 50 parts by mass or less, more preferably 40 parts by mass or less, even more preferably 30 parts by mass or less, even more preferably 20 parts by mass or less, and even more preferably 15 parts by mass or less, relative to 100 parts by mass of the polyester resin, amorphous resin, and / or second thermoplastic resin combined. By ensuring that the content is equal to or less than the upper limit, the effect of suppressing a decrease in laser weld strength tends to be further improved. In particular, from the viewpoint of improving the mechanical strength of the resulting molded article, the content of the elastomer is preferably 10 parts by mass or less, 7 parts by mass or less, 5 parts by mass or less, and 4 parts by mass or less, respectively, per 100 parts by mass of the total of the polyester resin and the amorphous resin and / or the second thermoplastic resin. The resin composition of the present embodiment may contain only one type of elastomer, or may contain two or more types. When two or more types are contained, the total amount is preferably in the above range.

[0070] <Reactive compounds> The resin composition of this embodiment may further contain a reactive compound (preferably an epoxy compound). The inclusion of a reactive compound tends to increase the weld strength. However, if the reactive compound also falls under the category of an elastomer, it is classified as an elastomer in this specification. The reactive compound is preferably a compound that can chemically react with the carboxyl or hydroxyl groups present at the terminals of the polybutylene terephthalate resin to cause a crosslinking reaction or chain extension. The reactive compound preferably contains at least one selected from the group consisting of epoxy compounds, carbodiimide compounds, compounds having an oxazoline group (ring), compounds having an oxazine group (ring), compounds having a carboxyl group, and compounds having an amide group. It is more preferable to contain at least one selected from epoxy compounds and carbodiimide compounds, and it is even more preferable to contain an epoxy compound. In particular, the resin composition of this embodiment preferably contains at least 90% by mass, more preferably at least 95% by mass, and particularly preferably at least 99% by mass of the reactive compounds as epoxy compounds. The epoxy compound is not particularly limited as long as it has one or more epoxy groups in one molecule, and a wide variety of known epoxy compounds can be used. The inclusion of an epoxy compound tends to broaden the range of laser irradiation conditions.

[0071] Examples of the epoxy compound include a glycidyl compound, an epoxy compound having an aromatic ring, and an alicyclic epoxy compound, and it is preferable to include at least an epoxy compound having an aromatic ring.

[0072] Specific examples of epoxy compounds include bisphenol A type epoxy compounds (including bisphenol A diglycidyl ether), bisphenol F type epoxy compounds (including bisphenol F diglycidyl ether), biphenyl type epoxy compounds (including bis(glycidyloxy)biphenyl), resorcinol type epoxy compounds (including resorcinol diglycidyl ether), novolac type epoxy compounds, epoxy compounds having an aromatic ring such as benzoic acid glycidyl ester, terephthalic acid diglycidyl ester, orthophthalic acid diglycidyl ester, methyl glycidyl ether, butyl glycidyl ether, 2-ethylhexyl glycidyl ether, decyl glycidyl ether, sucralose, glycidyl ether ... Examples of suitable diglycidyl ethers include (di)glycidyl ethers such as tearyl glycidyl ether, phenyl glycidyl ether, butylphenyl glycidyl ether, allyl glycidyl ether, neopentyl glycol diglycidyl ether, ethylene glycol diglycidyl ether, glycerin diglycidyl ether, and propylene glycol diglycidyl ether; paraffinic (e.g., saturated fatty acid) or olefinic (e.g., unsaturated fatty acid) (di)glycidyl esters such as sorbic acid glycidyl ester, adipic acid diglycidyl ester, epoxidized linseed oil, and epoxidized soybean oil; and alicyclic epoxy compounds such as vinylcyclohexene dioxide and dicyclopentadiene oxide. Among these, bisphenol A type epoxy compounds, novolac type epoxy compounds, bisphenol F type epoxy compounds, biphenyl type epoxy compounds, etc. are preferred, and orthocresol / novolac type epoxy resins (polyglycidyl ether compounds of o-cresol-formaldehyde polycondensates) are particularly preferred. Commercially available products include "Joncryl ADR4368C" (trade name: manufactured by BASF), Epicoat 1003 (trade name: manufactured by Mitsubishi Chemical Corporation), and Nippon Steel & Sumikin Chemical Co., Ltd. (trade name: YDCN704).

[0073] The epoxy compound preferably has a weight-average molecular weight of 15,000 or less, more preferably 10,000 or less. There is no particular lower limit to the weight-average molecular weight, but the weight-average molecular weight is preferably 100 or more, more preferably 300 or more. By setting the weight-average molecular weight within this range, the effects of the present embodiment tend to be more effectively exhibited.

[0074] The epoxy compound preferably has an epoxy equivalent of 100 g / eq or more, more preferably 150 g / eq or more, and more preferably 150 g / eq or more, and more preferably 1500 g / eq or less, more preferably 800 g / eq or less, and even more preferably 200 g / eq or less. By setting the epoxy equivalent to the lower limit or more, the flowability tends to be high and molding tends to be easy, while by setting it to the upper limit or less, the weld strength and the hydrolysis resistance of the welded body tend to be higher.

[0075] When the resin composition of this embodiment contains a reactive compound (preferably an epoxy compound), the content thereof is preferably 0.2 parts by mass or more, more preferably 0.3 parts by mass or more, and even more preferably 0.4 parts by mass or more, relative to 100 parts by mass of the polyester resin, amorphous resin, and / or second thermoplastic resin combined, and may be 1 part by mass or more, 2 parts by mass or more, depending on the application. By setting the content at or above the lower limit, the welding strength tends to be increased and the hydrolysis resistance of the resin composition tends to be improved. Furthermore, the upper limit of the content of the reactive compound is preferably 18 parts by mass or less, more preferably 15 parts by mass or less, even more preferably 10 parts by mass or less, even more preferably 5 parts by mass or less, even more preferably 3 parts by mass or less, and may even be 1 part by mass or less, relative to 100 parts by mass of the polyester resin, amorphous resin, and / or second thermoplastic resin combined. By setting the content at or below the upper limit, the flowability tends to be increased and the moldability tends to be improved. The resin composition of the present embodiment may contain only one type of reactive compound, or may contain two or more types. When two or more types are contained, the total amount is preferably in the above range.

[0076] <Silicone compounds> The resin composition of the present embodiment may contain a silicone compound. By containing a silicone compound, the resulting molded article tends to have better alkali resistance, hydrolysis resistance, and surface appearance. The type of silicone compound is not particularly limited, but it is preferably a high-molecular-weight silicone compound. The weight-average molecular weight of the silicone compound used in this embodiment is preferably 10,000 or more, more preferably 20,000 or more, even more preferably 30,000 or more, and even more preferably 40,000 or more, and is preferably 500,000 or less, more preferably 300,000 or less, even more preferably 100,000 or less, and even more preferably 80,000 or less.

[0077] The silicone compound may be blended as is, but is preferably blended as a masterbatch, which improves alkali resistance and hydrolysis resistance and prevents deterioration of the surface appearance and reduction in laser welding strength due to bleed-out of the silicone compound to the surface.

[0078] The silicone compound used in the masterbatch is an organosilicon compound with a siloxane bond as the backbone, in which organic groups are directly bonded to the silicon. Known organic groups directly bonded to silicon include methyl, ethyl, phenyl, vinyl, trifluoropropyl, and combinations thereof, and any known siloxane compound having these groups can be used without particular limitation. Siloxane compounds in which a portion of the organic group is substituted with a substituent having an epoxy group, amino group, polyether group, carboxyl group, mercapto group, ester group, chloroalkyl group, alkyl group with 3 or more carbon atoms, hydroxyl group, or the like can also be used. Siloxane compounds can be used alone or in combination of two or more.

[0079] Siloxane compounds are classified into silicone oils, silicone elastomers, and silicone resins (see "Silicone Materials Handbook," edited by Toray Dow Corning Co., Ltd., published August 1993). Any of the above can be used in the present invention, but silicone resins and silicone oils are preferred. Specific examples of silicone oils include oily silicones such as dimethylsilicone oil, phenylmethylsilicone oil, alkyl-modified silicone oil, fluorosilicone oil, polyether-modified silicone oil, aliphatic ester-modified silicone oil, amino-modified silicone oil, carboxylic acid-modified silicone oil, carbinol-modified silicone oil, epoxy-modified silicone oil, and mercapto-modified silicone oil.

[0080] Furthermore, the thermoplastic resin used in the masterbatch is preferably a resin incompatible with polybutylene terephthalate resin. By using a resin incompatible with polybutylene terephthalate as the masterbatch, the silicone compound is present at a high concentration in the incompatible resin dispersed in the polybutylene terephthalate, making it easier to exhibit effects such as alkali resistance. Examples of usable thermoplastic resins include polyolefin resins, polyamide resins, styrene-based resins, polyimide resins, polyetherimide resins, polyurethane resins, polyphenylene ether resins, polyphenylene sulfide resins, polysulfone resins, and polymethacrylate resins. Polyolefin resins are preferred, polyethylene resins are more preferred, and low-density polyethylene resins (LDPE resins) are even more preferred. stomach.

[0081] Various polyolefin resins can be used as the polyolefin resin, but preferred examples include polyethylene resins such as ethylene or propylene homopolymers, ethylene copolymers of ethylene with propylene, butene, hexene, octene, or vinyl acetate, and polypropylene resins such as propylene copolymers of propylene with butene, hexene, or octene. Specific preferred polyethylene resins include high-density polyethylene (HDPE), low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), and ethylene-vinyl acetate copolymer (EVA). Preferred polypropylene resins include polypropylene and propylene-ethylene copolymers. Among these, polyethylene resins are preferred, with high density polyethylene (HDPE), low density polyethylene (LDPE) and linear low density polyethylene (LLDPE) being more preferred, and low density polyethylene (LDPE) being particularly preferred.

[0082] There are no limitations on the production method or polymerization catalyst for the polyolefin resin, and any of various known production methods such as a solution method, bulk method, gas phase method, or high-pressure method, or any of methods using a radical initiator, Ziegler catalyst, chromium-based catalyst, or metallocene-based catalyst, etc. may be used.

[0083] The polyolefin resin may be used alone or in combination of two or more.

[0084] The masterbatch can be produced by a conventionally known method, for example, by mixing using a ribbon blender, a Henschel mixer, a Banbury mixer, a drum tumbler, a single-screw or multi-screw extruder, etc. Among these, a method using a Henschel mixer or a single-screw or multi-screw extruder is preferred, and a method using a single-screw or multi-screw extruder to melt-knead and pelletize is particularly preferred. By producing a masterbatch in this way and then melt-kneading it during production, the mechanical properties and sliding properties of the molded article tend to be better.

[0085] The masterbatch containing a silicone compound and a thermoplastic resin can be commercially available, and can be selected from, for example, the "Silicone Concentrate" series manufactured by Toray Dow Corning Co., Ltd.

[0086] The proportion of the silicone compound in the silicone compound masterbatch is preferably 5% by mass or more, more preferably 10% by mass or more, and is preferably 50% by mass or less, and even more preferably 40% by mass or less. The proportion of the thermoplastic resin in the silicone compound masterbatch is preferably 50% by mass or more, more preferably 60% by mass or more, and is preferably 95% by mass or less, and even more preferably 90% by mass or less.

[0087] When the resin composition of this embodiment contains a silicone compound, the content thereof is preferably 0.01 parts by mass or more, more preferably 0.1 parts by mass or more, even more preferably 0.5 parts by mass or more, even more preferably 0.8 parts by mass or more, relative to 100 parts by mass of the polyester resin, amorphous resin, and / or second thermoplastic resin combined, and is preferably 5 parts by mass or less, more preferably 3 parts by mass or less, and even more preferably 2 parts by mass or less. By setting the content at or above the lower limit, the alkali resistance and hydrolysis resistance of the resulting molded article tend to be further improved. Meanwhile, by setting the content at or below the upper limit, the surface appearance, basic physical properties, and laser welding strength of the resulting molded article tend to be further improved. The resin composition of the present embodiment may contain only one type of silicone compound, or may contain two or more types. When two or more types are contained, the total amount is preferably in the above range.

[0088] <Inorganic fillers> The resin composition of the present embodiment may contain an inorganic filler, which can increase the mechanical strength of the resulting absorbing resin member. The inorganic filler may be a fibrous inorganic filler such as glass fiber, carbon fiber, basalt fiber, wollastonite, or potassium titanate fiber. Granular or amorphous fillers such as calcium carbonate, titanium oxide, feldspar minerals, clay, or glass beads, or scaly fillers such as glass flakes or graphite, may also be used. Among these, fibrous fillers, particularly glass fiber, are preferred in terms of mechanical strength, rigidity, and heat resistance. The glass fibers are made of glass compositions such as A-glass, C-glass, E-glass, S-glass, D-glass, M-glass, and R-glass, and E-glass (alkali-free glass) is particularly preferred because it does not adversely affect the polybutylene terephthalate resin. Examples of fibers include those having a cross-sectional shape when cut perpendicular to the length direction that is circular, elliptical, polygonal, or the like, and which have a fibrous appearance and are sufficiently long compared to the cross-section.

[0089] The glass fiber used in the resin composition of this embodiment may be a single fiber or a plurality of single fibers twisted together. The glass fiber may be in the form of a "glass roving" in which a single fiber or a plurality of twisted fibers are continuously wound, a "chopped strand" cut to a length of 1 to 10 mm, or a "milled fiber" pulverized to a length of 10 to 500 μm, but chopped strand is preferred. Such glass fiber is readily available and is commercially available from Asahi Fiber Glass Co., Ltd. under the trade names "Glaslon Chopped Strand" and "Glaslon Milled Fiber." Glass fibers of different forms can also be used in combination.

[0090] In this embodiment, glass fibers having an irregular cross-sectional shape are also preferred. The irregular cross-sectional shape has a flattening ratio, expressed as the ratio of the major axis to the minor axis (D2 / D1), where D2 is the major axis and D1 is the minor axis of a cross section perpendicular to the longitudinal direction of the fiber, of, for example, 1.5 to 10, preferably 2.5 to 10, more preferably 2.5 to 8, and even more preferably 2.5 to 5. For such flat glass, see paragraphs 0065 to 0072 of JP 2011-195820 A, the contents of which are incorporated herein by reference.

[0091] When the resin composition of this embodiment contains an inorganic filler (preferably glass fiber), the content thereof is preferably 25 parts by mass or more, more preferably 30 parts by mass or more, even more preferably 35 parts by mass or more, even more preferably 40 parts by mass or more, and even more preferably 45 parts by mass or more, relative to 100 parts by mass of the polyester resin, amorphous resin, and / or second thermoplastic resin combined. By setting the content at or above the lower limit, the mechanical hardness of the resulting absorbent resin member tends to be further improved. The upper limit of the content of the inorganic filler is preferably 100 parts by mass or less, more preferably 80 parts by mass or less, even more preferably 70 parts by mass or less, even more preferably 60 parts by mass or less, and even more preferably 55 parts by mass or less, relative to 100 parts by mass of the polyester resin, amorphous resin, and / or second thermoplastic resin combined. By setting the content at or below the upper limit, the effect of suppressing a decrease in tensile elongation tends to be further improved.

[0092] Furthermore, when the resin composition of this embodiment contains an inorganic filler (preferably glass fiber), its content in the resin composition is preferably 20% by mass or more, and more preferably 25% by mass or more. By making it equal to or greater than the lower limit, the mechanical hardness of the resulting absorbent resin member tends to be further improved. The upper limit of the content of the inorganic filler in the resin composition is preferably 50% by mass or less, more preferably 45% by mass or less, even more preferably 40% by mass or less, and may be 35% by mass or less. By making it equal to or less than the upper limit, the effect of suppressing a decrease in tensile elongation tends to be further improved. The resin composition of the present embodiment may contain only one type of inorganic filler, or may contain two or more types. When two or more types are contained, the total amount is preferably in the above range.

[0093] <Stabilizer> The resin composition of this embodiment may contain a stabilizer. Examples of the stabilizer include a phenol-based stabilizer (preferably a hindered phenol-based stabilizer), a hindered amine-based stabilizer, a phosphorus-based stabilizer, and a sulfur-based stabilizer. Among these, the phenol-based stabilizer, the phosphorus-based stabilizer, and the sulfur-based stabilizer are preferred. Specific examples of stabilizers include the descriptions in paragraphs 0046 to 0057 of JP 2018-070722 A, the descriptions in paragraphs 0030 to 0037 of JP 2019-056035 A, the descriptions in paragraphs 0066 to 0078 of WO 2017 / 038949 A, and paragraphs 0051 to 0060 of JP 2020-147662 A. The contents of these descriptions can be taken into consideration, and are incorporated herein by reference.

[0094] The content of the stabilizer in the resin composition of this embodiment is preferably 0.01 parts by mass or more, and more preferably 0.10 parts by mass or more, per 100 parts by mass of the polyester resin, amorphous resin, and / or second thermoplastic resin combined. The upper limit of the content of the stabilizer is preferably 4 parts by mass or less, more preferably 3 parts by mass or less, and even more preferably 2 parts by mass or less, per 100 parts by mass of the polyester resin, amorphous resin, and / or second thermoplastic resin combined. The resin composition of the present embodiment may contain only one stabilizer, or may contain two or more stabilizers. When two or more stabilizers are contained, the total amount is preferably in the above range.

[0095] <Release agent> The resin composition of the present embodiment may contain a release agent, such as an aliphatic carboxylic acid, an ester of an aliphatic carboxylic acid and an alcohol, an aliphatic hydrocarbon compound having a number average molecular weight of 200 to 15,000, wax, or polysiloxane-based silicone oil. For details, please refer to paragraphs 0112 to 0121 of International Publication No. 2020 / 013127, the contents of which are incorporated herein by reference.

[0096] The content of the release agent is usually 0.001 part by mass or more, preferably 0.01 part by mass or more, and usually 2 parts by mass or less, preferably 1 part by mass or less, relative to 100 parts by mass of the total of the polyester resin, the amorphous resin, and / or the second thermoplastic resin. By setting the content of the release agent to be at least the lower limit of the above range, sufficient releasability effect is easily obtained, and by setting the content of the release agent to be at most the upper limit of the above range, sufficient hydrolysis resistance is obtained and mold contamination during injection molding is less likely to occur. The resin composition of the present embodiment may contain only one type of release agent, or may contain two or more types. When two or more types are contained, the total amount is preferably in the above range.

[0097] <Other ingredients> The resin composition may contain other components in addition to those described above, as necessary, as long as the desired physical properties are not significantly impaired. Examples of other components include various resin additives. Note that the other components may be contained alone or in any combination and ratio of two or more. Specific examples include flame retardants, flame retardant auxiliaries, nucleating agents, ultraviolet absorbers, antistatic agents, anti-fogging agents, anti-blocking agents, flow improvers, plasticizers, dispersants, and antibacterial agents. In the resin composition of the present embodiment, the polyester resin, amorphous resin and / or second thermoplastic resin, carbon black, and any other components blended as necessary total 100% by mass, and the polyester resin, amorphous resin and / or second thermoplastic resin, carbon black, reactive compound, elastomer, inorganic filler, stabilizer, and release agent preferably total 90 to 100% by mass, more preferably 95 to 100% by mass, and even more preferably 99 to 100% by mass. The resin composition of the present embodiment is a composition containing a polyester resin and an amorphous resin and / or a second thermoplastic resin (absolute value of difference in SP value from the polyester resin (|SP 1 -SP 2 The thermoplastic resin may or may not contain a thermoplastic resin other than the thermoplastic resin in which |) is 0 to 3.0. The resin composition of this embodiment may be configured to be substantially free of other thermoplastic resins than the polyester resin, amorphous resin, and / or second thermoplastic resin. "Substantially free" means that the content of the other thermoplastic resins is 10% by mass or less of the total amount of the polyester resin, amorphous resin, and / or second thermoplastic resin contained in the resin composition, preferably less than 5% by mass, more preferably less than 3% by mass, and even more preferably less than 1% by mass.

[0098] A preferred example of the resin composition of the present embodiment is a resin composition that contains, relative to 100 parts by mass of polybutylene terephthalate resin, 5 to 20 parts by mass of an elastomer, 0.2 to 1 part by mass of a reactive compound, 0.01 to 1 part by mass of a release agent, 0.01 to 2 parts by mass of a stabilizer, and 0.01 to 0.4 parts by mass of carbon black, and in 100% by mass of the amorphous resin contained in the resin composition, the amount of amorphous resin derived from the carbon black masterbatch is more than 90% by mass and 100% by mass or less. In the above, the total amount of the polybutylene terephthalate resin, elastomer, reactive compound, release agent, stabilizer, and carbon black preferably accounts for 90 to 100 mass %, more preferably 95 to 100 mass %.

[0099] Another preferred example of the resin composition of the present embodiment is a resin composition containing 100 parts by mass of a polybutylene terephthalate resin (preferably an isophthalic acid-modified polybutylene terephthalate resin in which 1 to 30 mol % (preferably 5 to 25 mol %) of the terephthalic acid component in the polybutylene terephthalate resin is modified with isophthalic acid), 1 to 4 parts by mass of an elastomer, 2 to 5 parts by mass of a reactive compound, 0.01 to 5 parts by mass of a silicone compound, 0.01 to 1 part by mass of a release agent, 0.01 to 2 parts by mass of a stabilizer, and 0.01 to 0.4 parts by mass of carbon black, in which the amount of amorphous resin derived from the carbon black masterbatch is more than 90% by mass and not more than 100% by mass of 100% by mass of the amorphous resin contained in the resin composition. In the above, the total amount of the polybutylene terephthalate resin, elastomer, reactive compound, silicone compound, release agent, stabilizer, and carbon black preferably accounts for 90 to 100 mass %, more preferably 95 to 100 mass %.

[0100] <<Physical Properties>> Next, preferred values ​​for the resin composition of this embodiment will be described. The resin composition of the present embodiment preferably has excellent mechanical strength. The resin composition of this embodiment is molded into a 4 mm thick ISO test piece, and the bending strength according to ISO 178 is preferably 100 MPa or more, more preferably 150 MPa or more. There is no particular upper limit, but for example, 300 MPa or less is practical, and even 250 MPa or less will fully satisfy the performance requirements.

[0101] The resin composition of this embodiment was molded into an ISO test piece having a thickness of 4 mm, and the notched Charpy impact strength according to ISO179 was 5 kJ / m 2 It is preferable that the concentration is 7 kJ / m or more. 2 The upper limit is not particularly specified, but it is preferably 50 kJ / m 2 The following is practical: 30 kJ / m 2 The following is sufficient to meet the performance requirements.

[0102] The resin composition of the present embodiment preferably has excellent fluidity. Specifically, the resin composition has a melt volume rate (MVR) of 5.0 cm per unit time under the conditions of a temperature of 250°C and a load of 5.0 kgf according to JIS K7210. 3 / 10 minutes or more is preferable, 13.0 cm 3 / 10 minutes or more is preferable, 15.0 cm 3 The upper limit of the MVR is, for example, 20 cm / 10 minutes or more. 3 / It may be less than 10 minutes.

[0103] <Applications of resin composition> The resin composition of the present embodiment can be applied to various storage containers, electrical and electronic equipment parts, office automation (OA) equipment parts, home appliance parts, machine mechanism parts, vehicle mechanism parts, etc. In particular, it can be suitably used for food containers, chemical containers, oil and fat product containers, hollow vehicle parts (various tanks, intake manifold parts, camera housings), vehicle electrical parts (various control units, ignition coil parts, etc.), motor parts, various sensor parts, connector parts, switch parts, breaker parts, relay parts, coil parts, transformer parts, lamp parts, etc.

[0104] More specifically, the resin composition of this embodiment is preferably used on the laser light absorbing side during laser welding. That is, one example of the use of the resin composition of this embodiment is as an absorbing resin member during laser welding. The shape of the absorbing resin member is not particularly limited, but since the members are joined together by laser welding, it usually has a shape that has at least a surface contact area (flat surface, curved surface). In laser welding, the laser light that has passed through the transmitting resin member is absorbed by the absorbing resin member, melting it and welding the two members together.

[0105] The resin composition of this embodiment can also be used for laser marking, and is particularly suitable as a resin composition used on the laser light absorbing side during laser welding and for laser marking.

[0106] On the other hand, the laser-transmitting resin member (transmitting resin member) used during laser welding is preferably formed from a laser-transmitting resin composition containing a polyester resin and a light-transmitting dye, and has a light transmittance of 5% or more (upper limit, for example, 50% or less) at a wavelength of 1064 nm when the laser-transmitting resin composition is molded to a thickness of 1.5 mm. The details of the polyester resin are the same as those of the polyester resin described in the section on resin composition above, and the preferred ranges are also the same. The light-transmitting dye will be described in detail later.

[0107] The shape of the transmissive resin member is not particularly limited, but since the members are joined together by laser welding, it usually has a shape that has at least a surface contact area (flat surface, curved surface). In laser welding, the laser light that passes through the transmissive resin member is absorbed by the absorbing resin member, melting it and welding the two members together. Here, the thickness of the transmissive resin member through which the laser light passes (the thickness in the laser transmission direction at the portion through which the laser light passes) can be determined as appropriate, but is, for example, 5 mm or less, preferably 4 mm or less. The lower limit is, for example, 100 μm or more.

[0108] The laser-transmittable resin composition may or may not contain a polycarbonate resin. The details of the polycarbonate resin are the same as those of the polycarbonate resin described above in the section on the resin composition of this embodiment, and the preferred ranges are also the same.

[0109] The laser-transmittable resin composition may contain an elastomer. Details of the elastomer are the same as those of the elastomer described above in the section on the resin composition of this embodiment, and the preferred ranges are also the same. The laser-transmittable resin composition may contain a reactive compound. Details of the reactive compound are the same as those described above in the section on the resin composition of this embodiment, and the preferred ranges are also the same. The laser-transmittable resin composition may contain an inorganic filler. Details of the inorganic filler are the same as those of the inorganic filler described above in the section on the resin composition of this embodiment, and the preferred ranges are also the same. The laser-transmittable resin composition may contain a release agent and / or a stabilizer. Details of the release agent and / or stabilizer are the same as those of the release agent and / or stabilizer described above in the section on the resin composition of this embodiment, and the preferred ranges are also the same.

[0110] <<Light-transmitting dye>> Next, the light-transmitting dye contained in the laser-transmitting resin composition will be described. The light-transmitting dye is not particularly limited as long as it transmits at least a certain percentage of the laser for laser welding, and any known dye can be used. The light-transmitting dye includes, for example, a dye that, when a total of 100% by mass of a polybutylene terephthalate resin (e.g., Novaduran (registered trademark) 5008), 30% by mass of glass fiber (e.g., Nippon Electric Glass Co., Ltd., product name: T-127), and 0.2% by mass of a dye (a dye believed to be a light-transmitting dye) is blended, and the light transmittance is measured, has a transmittance of 5% or more. Furthermore, by blending the transparent dye of this embodiment, for example, the transmittance at a wavelength of 1064 nm can be made 5% or more when the laser-transmitting resin composition is molded to a thickness of 1.5 mm. The light-transmitting pigment is usually a dye. The light-transmitting dye can be appropriately selected depending on the application, and its color is not particularly limited. The light-transmitting dye used in this embodiment is preferably a black dye and / or a black dye composition containing two or more chromatic dyes. The black dye composition refers to a composition that exhibits black by combining two or more chromatic dyes such as red, blue, and green. A first embodiment of the black pigment composition contains a green pigment and a red pigment. A second embodiment of the black pigment composition contains a red pigment, a blue pigment, and a yellow pigment. Specific examples of the light-transmitting dye include nigrosine, naphthalocyanine, aniline black, phthalocyanine, porphyrin, perinone, quaterrylene, azo, azomethine, anthraquinone, pyrazolone, squaric acid derivatives, perylene, chromium complexes, and immonium. Azomethine, anthraquinone, and perinone are preferred, and anthraquinone and perinone are more preferred.

[0111] Examples of commercially available products include colorants e-BIND LTW-8731H and e-BIND LTW-8701H manufactured by Orient Chemical Industry Co., Ltd.; colorants Plast Yellow 8000, Plast Red M 8315, Plast Red 8370, and Oil Green 5602 manufactured by Arimoto Chemical Co., Ltd.; colorants Macrolex Yellow 3G, Macrolex Red EG, and Macrolex Green 5B manufactured by LANXESS; and colorants KP Plast HK, KP Plast Red HG, KP Plast Red H2G, KP Plast Blue R, KP Plast Blue GR, and KP Plast Green G manufactured by Kiwa Chemical Industry Co., Ltd. Furthermore, dyes described in Japanese Patent No. 4157300 and Japanese Patent No. 4040460 can also be used, the contents of which are incorporated herein by reference.

[0112] The laser-transmittable resin composition used in this embodiment preferably contains 0.001 to 5 parts by mass of the light-transmittable dye relative to 100 parts by mass of the polyester resin. The lower limit of the content is preferably 0.01 parts by mass or more, more preferably 0.05 parts by mass or more, even more preferably 0.1 parts by mass or more, and even more preferably 0.2 parts by mass or more. By setting the content at or above the lower limit, the light-transmittable resin member is colored, thereby enhancing the design of the laser-welded product. The upper limit of the content is preferably 3 parts by mass or less, more preferably 2 parts by mass or less, even more preferably 1 part by mass or less, even more preferably 0.8 parts by mass or less, and even more preferably 0.5 parts by mass or less. Setting the content at or below the upper limit effectively suppresses bleed-out of the light-transmittable dye. The laser-transmittable resin composition may contain only one type of light-transmittable dye, or may contain two or more types. When two or more types are contained, the total amount is preferably in the above range.

[0113] The laser-transmittable resin composition may contain other components in addition to those described above, as necessary, as long as the desired physical properties are not significantly impaired. Examples of such other components include various resin additives. The other components may be contained alone or in any combination and ratio of two or more. Specific examples include flame retardants, flame retardant auxiliaries, nucleating agents, ultraviolet absorbers, antistatic agents, anti-fogging agents, anti-blocking agents, flow improvers, plasticizers, dispersants, and antibacterial agents. In the laser-transmittable resin composition used in the present embodiment, the polyester resin, the light-transmitting dye, and any other components blended as required account for 100% by mass in total, and the polyester resin, the light-transmitting dye, and any other components blended as required, the polycarbonate resin, the flame retardant, the flame retardant aid, the anti-dripping agent, the reactive compound, the elastomer, the inorganic filler, the stabilizer, and the release agent, account for preferably 90 to 100% by mass in total, more preferably 95 to 100% by mass, and even more preferably 99 to 100% by mass.

[0114] <Method of manufacturing resin composition> The resin composition and laser-transmittable resin composition of this embodiment can be produced by a conventional method for preparing a resin composition. Typically, the components and various optional additives are thoroughly mixed together and then melt-kneaded in a single-screw or twin-screw extruder. Alternatively, the resin composition can be prepared by not premixing the components, or by premixing only a portion of the components, feeding the mixture into an extruder using a feeder, and melt-kneading the mixture. The resin composition of the present embodiment particularly preferably includes adding and melt-kneading 0.01 part by mass or more and 0.4 part by mass or less of carbon black to a total of 100 parts by mass of the polyester resin and the amorphous resin and / or the second thermoplastic resin, and adding at least a portion of the amorphous resin and / or the second thermoplastic resin as a masterbatch of the carbon black. When a fibrous inorganic filler such as glass fiber is used, it is also preferable to feed it from a side feeder midway through the cylinder of the extruder. The heating temperature during melt-kneading can usually be selected appropriately from the range of 220 to 300°C. If the temperature is too high, decomposition gases are likely to be generated, which may cause the material to become opaque. Therefore, it is desirable to select a screw configuration that takes into account shear heat generation, etc. To suppress decomposition during kneading and subsequent molding processes, it is desirable to use antioxidants and heat stabilizers.

[0115] <Method of manufacturing the absorbent resin member and the permeable resin member> The manufacturing method of the absorbent resin member and the permeable resin member is not particularly limited, and any molding method generally used for polyester resin compositions can be used. Examples include injection molding, ultra-high speed injection molding, injection compression molding, two-color molding, gas-assisted or other hollow molding methods, molding using an insulated mold, molding using a rapidly heated mold, foam molding (including supercritical fluid), insert molding, IMC (in-mold coating molding), extrusion molding, sheet molding, thermoforming, rotational molding, lamination molding, press molding, and blow molding, among which injection molding is preferred. For details of injection molding, please refer to the description in paragraphs 0113 to 0116 of Japanese Patent No. 6183822, the contents of which are incorporated herein by reference.

[0116] <Method of manufacturing laser welded products> Next, a laser welding method will be described. In this embodiment, the transmissive resin member and the absorbing resin member can be laser-welded to form a laser-welded product. By laser welding, the transmissive resin member and the absorbing resin member can be firmly welded together without using an adhesive. The transparent resin member and the absorbing resin member may be laser welded by any known laser welding method, but galvano-scanning laser welding is suitable. Galvano-scanning laser welding, also known as quasi-simultaneous welding, is a method in which a laser beam is scanned using a built-in galvanometer mirror. By using galvano-scanning laser welding, the entire welded area is heated almost simultaneously, which tends to reduce residual stress in the resulting laser-welded product. That is, a preferred example of a method for producing a laser-welded product of this embodiment is to use the kit of this embodiment or the resin composition of this embodiment and a laser-transparent resin composition that has a light transmittance of 5% or more and less than 25% at a wavelength of 1064 nm when molded to a thickness of 1.5 mm, and to perform galvanoscanning laser welding.

[0117] The laser light source used for laser welding can be determined depending on the absorption wavelength of the light of the light-absorbing dye, and a laser with a wavelength in the range of 800 to 1100 nm is preferred. Examples of the type of laser light to be irradiated include solid-state lasers, fiber lasers, semiconductor lasers, gas lasers, and liquid lasers. For example, YAG (yttrium aluminum garnet crystal) lasers (wavelengths of 1064 nm and 1070 nm) and LD (laser diode) lasers (wavelengths of 808 nm, 840 nm, 940 nm, and 980 nm) are preferred. Laser light with wavelengths of 940 nm, 980 nm, and 1070 nm are particularly preferred.

[0118] The laser focal diameter is preferably 0.1 mm or more, more preferably 0.2 mm or more, and even more preferably 0.5 mm or more. By setting it to the upper limit or less, the weld strength of the laser welded portion can be further increased. Furthermore, the laser irradiation diameter is preferably 30 mm or less, more preferably 10 mm or less, and even more preferably 3.0 mm or less. By setting it to the lower limit or more, the weld width can be more effectively controlled. The focal diameter of the laser light can be selected according to the width and height of the welding surface. The laser light may be focused or defocused on the joining surface, and it is preferable to select an appropriate method depending on the desired welded body.

[0119] The laser output is preferably 1 W or more, more preferably 10 W or more, even more preferably 30 W or more, and even more preferably 100 W or more. By setting the laser output at or above the lower limit, sufficient welding strength can be obtained even with a short welding time. Furthermore, the laser output is preferably 1000 W or less, more preferably 500 W or less, even more preferably 400 W or less, and even more preferably 300 W or less. By setting the laser output at or below the upper limit, the cost of laser welding equipment can be effectively reduced. The laser irradiation speed is preferably 10 mm / s or more, more preferably 30 mm / s or more, even more preferably 50 mm / s or more, and even more preferably 500 mm / s or more. By setting the laser irradiation speed at or above the lower limit, residual stress in the laser welded product can be more effectively reduced. Furthermore, the laser irradiation speed is preferably 20,000 mm / s or less, more preferably 10,000 mm / s or less, even more preferably 5,000 mm / s or less, and even more preferably 3,000 mm / s or less. By setting the laser irradiation speed at or below the upper limit, more sufficient welding strength can be obtained for the welded product. Furthermore, with regard to the laser scanning method, it is preferable to adjust the laser output, intended welding line, scanning speed, and / or scanning method according to the shape of the joining surfaces from the viewpoints of welding efficiency, welding strength, welding appearance, and equipment load.

[0120] More specifically, for example, when welding a transmissive resin member and an absorptive resin member, the portions of the two members to be welded are first brought into contact with each other. At this time, the welded portions of the two members are preferably in surface contact, and may be flat surfaces, curved surfaces, or a combination of flat and curved surfaces. To maintain the overlapped state, a transparent plate such as a glass plate, quartz plate, or acrylic plate may be placed on top of the transmissive resin member, i.e., on the laser irradiation side, and pressure may be applied. Placing a glass or quartz plate in particular is suitable for promoting the dissipation of heat generated during laser welding and achieving a good appearance. Pressure may also be applied using a metal plate surrounding the periphery of the portion of the transmissive resin member to be welded. Next, a laser beam is irradiated from the transparent resin member side. If necessary, a lens may be used to focus the laser beam at the interface between the two. The focused beam passes through the transparent resin member and is absorbed near the surface of the absorptive resin member, generating heat and melting it. The heat is then transferred to the transparent resin member by thermal conduction, melting it and forming a molten pool at the interface between the two. After cooling, the two are bonded together. In this way, the laser-welded product of the transmitting resin member and the absorbing resin member has high weld strength. Note that the laser-welded product in this embodiment is intended to include not only finished products and parts, but also members that form part of these products and parts.

[0121] The laser welded product between the laser-transmitting resin member formed from the laser-transmitting resin composition and the laser-absorbing resin member formed from the resin composition can have a laser weld strength of 800 N or more, 1000 N or more, 1100 N or more, or even 1200 N or more. There is no particular upper limit to the laser weld strength, but a practical upper limit is 4000 N or less. The laser weld strength is measured as described in the examples below.

[0122] <Kits and laser welded parts> The kit of this embodiment includes the resin composition of this embodiment and a laser-transmittable resin composition. In the kit, the resin composition of this embodiment serves as a laser-absorbent resin composition. Such a kit has excellent laser weldability and is preferably used as a kit for producing a molded product (laser-welded product) by laser welding. Furthermore, laser marking can also be performed. In other words, the resin composition of the present embodiment included in the kit serves as a laser-ray-absorbent resin composition, and a molded article formed from such a laser-ray-absorbent resin composition becomes an absorbing resin member for laser light during laser welding. Furthermore, the kit of the present embodiment may be a kit including a laser-absorbing resin member formed from the resin composition of the present embodiment and a laser-transmittable resin composition containing a polyester resin and a light-transmitting dye. The laser-welded product of this embodiment can be produced by a production method including irradiating a laser with a laser to a laser-absorbent resin member formed from the resin composition of this embodiment to perform laser marking, and laser welding the laser-absorbent resin member to a laser-transmittable resin member formed from a laser-transmittable resin composition containing a polyester resin and a light-transmitting dye. When producing the laser-welded product of this embodiment, the laser welding and the laser marking may be performed in either order, or may be performed simultaneously. The laser-absorbent resin member formed from the resin composition of this embodiment can be laser-marked.

[0123] Molded articles obtained by laser welding in this embodiment have good mechanical strength, high weld strength, and minimal damage to the resin due to laser irradiation. Therefore, they can be used in a variety of applications, such as various storage containers, electrical and electronic equipment parts, office automation (OA) equipment parts, home appliance parts, mechanical mechanism parts, and vehicle mechanism parts. They are particularly suitable for food containers, pharmaceutical containers, oil and fat product containers, hollow vehicle parts (various tanks, intake manifold parts, camera housings), vehicle electrical parts (various control units, ignition coil parts, etc.), automotive electronic and sensor parts (housings for millimeter-wave radar, LiDAR, ECU cases, sonar sensors, etc.), electronically controlled throttle bodies, motor parts, various sensor parts, connector parts, switch parts, breaker parts, relay parts, coil parts, transformer parts, and lamp parts. The resin composition and kit of this embodiment are particularly suitable for in-vehicle camera parts, in-vehicle camera modules including in-vehicle camera parts, millimeter-wave radar modules, sensor modules, and electric parking brake (EPB) parts. [Example]

[0124] The present invention will be explained in more detail below with reference to examples. The materials, amounts used, ratios, processing details, processing procedures, etc. shown in the following examples can be appropriately changed without departing from the spirit of the present invention. Therefore, the scope of the present invention is not limited to the specific examples shown below. If the measuring instruments used in the examples are difficult to obtain due to discontinuation or the like, measurements can be made using other instruments with equivalent performance.

[0125] 1.Raw materials The following raw materials were used: [Table 1]

[0126] [Table 2]

[0127] 2. Examples 1 to 5 and Comparative Examples 1 to 6 <Production of Resin Composition (Pellets)> As shown in Tables 3 to 5, all ingredients except for the glass fiber were placed in a stainless steel tumbler and mixed with stirring for 1 hour. The components in Tables 3 to 5 are expressed in parts by mass. The resulting mixture was placed in the main hopper of a 30 mm vent-type twin-screw extruder (manufactured by The Japan Steel Works, Ltd., "TEX30α"), and the glass fiber (GF) was fed from the seventh side feeder from the hopper. The mixture was kneaded and extruded into strands under the following conditions: extruder barrel temperatures C1 to C15 were set to 260°C, the die was set to 250°C, the screw rotation speed was set to 200 rpm, and the output rate was set to 40 kg / hour, yielding pellets of the resin composition.

[0128] <MVR of resin composition> The pellets obtained above were subjected to melt volume rate (MVR, unit: cm) measurement at a temperature of 250°C and a load of 5.0 kgf in accordance with JIS K7210. 3 / 10min) was measured. For the measurement, a melt indexer manufactured by Takara Industries Co., Ltd. was used. The higher the MVR, the better the liquidity.

[0129] <Bending properties> The pellets obtained above were dried at 110°C for 5 hours, and then injection-molded into 4 mm thick ISO test specimens using an injection molding machine ("J85AD" manufactured by The Japan Steel Works, Ltd.) at a cylinder temperature of 250°C and a mold temperature of 80°C. In accordance with ISO178, the flexural strength (unit: MPa) and flexural modulus (unit: MPa) were measured at a temperature of 23°C using the above ISO tensile test pieces (4 mm thick).

[0130] <Notched Charpy impact strength> The pellets obtained above were dried at 110°C for 5 hours, and then injection-molded into 4 mm thick ISO test specimens using an injection molding machine ("J85AD" manufactured by The Japan Steel Works, Ltd.) at a cylinder temperature of 250°C and a mold temperature of 80°C. The notched Charpy impact strength was measured according to ISO179.

[0131] <Disc warpage> Using the above resin composition, a 100 mm diameter, 1.6 mm thick disk was molded using an injection molding machine (Nissei Plastic Industrial Co., Ltd., "NEX80-9E") under conditions of a cylinder temperature of 260°C, a mold temperature of 80°C, a filling time of 0.5 seconds, and a dwell pressure of 50% of the peak pressure using a side gate mold. After molding, the disk was left overnight in an environment of 23°C and 50% RH, and the amount of warpage (unit: mm) of the disk was measured using a Keyence Corporation three-dimensional measuring machine (VL series). Each sample was measured five times, and the average value was calculated.

[0132] <Laser welding strength> <<Production of laser-transmitting resin composition (pellets)>> The following materials were used as raw materials for the laser-transmittable resin composition. Polybutylene terephthalate resin (Mitsubishi Chemical Corporation 5008-C): 47 parts by mass Polycarbonate resin (Mitsubishi Engineering Plastics H-4000FN): 20 parts by weight Nucleating agent (Hayashi Kasei Micron White 5000S): 0.005 parts by mass Stabilizer (ADEKA ADK STAB AX-71): 0.1 parts by mass Stabilizer (ADEKA ADK STAB AO-60): 0.2 parts by mass Reactive compound (CNE220 manufactured by Changchun Co., Ltd.): 1.0 parts by mass Release agent (Clariant Licowax E): 0.4 parts by mass Dye 1 (Plast Red 8370 manufactured by Arimoto Chemical Co., Ltd.): 0.42 parts by mass Dye 2 (Kiwa Kagaku Kogyo Co., Ltd. KP Plast Blue R): 0.45 parts by mass Dye 3 (Kiwa Kagaku Kogyo Co., Ltd. KP Plast Yellow HK): 0.38 parts by mass Inorganic pigment (Tokan Material Technology Co., Ltd. 42-920A): 0.1 parts by mass Glass (Nippon Electric Glass Co., Ltd. T-127): 30 parts by weight

[0133] All of the above ingredients except the glass fiber were placed in a stainless steel tumbler and mixed under stirring for 1 hour. The resulting mixture was placed in the main hopper of a 30 mm vent-type twin-screw extruder (manufactured by The Japan Steel Works, Ltd., "TEX30α"), with the glass fiber (GF) fed from the seventh side feeder from the hopper. The extruder barrel temperatures C1 to C15 were set at 260°C, the die at 250°C, the screw rotation speed at 200 rpm, and the output rate at 40 kg / hour. The mixture was then kneaded and extruded into strands to produce a laser-transmittable resin composition (pellets).

[0134] <<Transmittance of transparent resin material>> The laser-transmittable resin composition pellets were dried at 120°C for 7 hours, and then an injection molding machine (NEX80-9E manufactured by Nissei Plastic Industrial Co., Ltd.) was used to injection-mold a 60 mm x 60 mm x 1.5 mm thick transmittance measurement (transmittable resin member) plate for transmittance measurement under injection conditions of a cylinder temperature of 260°C, a mold temperature of 60°C, and an injection speed of 90 mm / sec. The transmittance (%) at a wavelength of 1064 nm was measured using an ultraviolet-visible-near-infrared spectrophotometer from a point 45 mm from the gate side and at the center of the width of the test plate, and the transmittance was found to be 41%. The ultraviolet-visible-near-infrared spectrophotometer used was a Shimadzu UV-3100PC with an integrating sphere.

[0135] <<Production of transparent resin parts>> The laser-transmittable resin composition obtained above was dried at 120°C for 7 hours, and then molded using an injection molding machine ("J55" manufactured by The Japan Steel Works, Ltd.) at a cylinder temperature of 260°C and a mold temperature of 60°C to produce a molded product (laser-transmittable resin member I) with a thickness of 1.5 mm, as shown in Figure 1.

[0136] <<Production of absorbent resin components>> The light-absorbing resin pellets obtained above were dried at 120°C for 7 hours, and then molded using an injection molding machine ("J55" manufactured by The Japan Steel Works, Ltd.) at a cylinder temperature of 260°C and a mold temperature of 60°C to produce a molded product (absorbent resin member II) with a rib thickness of 1.0 mm, as shown in Figure 2.

[0137] As shown in Figure 3, the transparent resin member and the absorbing resin member were assembled by placing a lid-shaped transparent resin member I on top of a box-shaped absorbing resin member II, and a laser light source was positioned vertically above the flange, which was the overlapping part of the transparent resin member I and the absorbing resin member II. A pressing force of 4.92 N / mm (extrusion force during welding) was applied inward from both sides in the thickness direction to the overlapping part of the transparent resin member I and the absorbing resin member II using a glass plate, and a laser was irradiated under the following conditions to obtain a laser-welded product. The welding equipment is as follows:

[0138] <<Galvano scanning laser welding>> Laser device: IPG YLR-300-AC-Y14 Wavelength: 1070nm Collimator: 7.5mm Laser Type: Fiber Laser power: 150W Galvanometer scanner: ARGES Fiber Elephants21 Aperture: 21mm Laser irradiation speed: 900mm / s Laser irradiation cycles: 20 or 25 cycles Welded part circumference: 137mm The laser beam was defocused and the position of the laser scanner was adjusted so that the spot diameter irradiated on the welding surface was 2 mm.

[0139] <<Laser welding strength measurement>> As shown in Figure 4, holes 21 and 22 were drilled, and welding strength measuring jigs 23 and 24 were placed inside. Then, measuring jigs 25 and 26 were inserted from the top and bottom of the box body made of the permeable resin member I and the absorbent resin member II prepared above, respectively, and connected to the jigs 23 and 24 stored inside. The boxes were then pulled up and down (pulling speed: 5 mm / min), and the strength (welding strength) at which the permeable resin member I and the absorbent resin member II separated was measured. The equipment used was a 1t Tensilon universal testing machine (load cell 10 kN) manufactured by ORIENTEC.

[0140] <Laser marking ability> The absorbent resin member obtained above was laser-marked in a square of 10 mm x 10 mm under the following conditions at the center thereof, and was evaluated on a four-level scale of A to D as shown below. Laser marking device: Panasonic LP-Z310 Laser type: Yb fiber laser (wavelength 1064nm) Laser power: 30W Scan speed: 600mm / s Print pulse period: 50 μs <<Evaluation>> After laser marking, the visibility of the marked area compared to the non-marked area was confirmed by visual observation and evaluated according to the following criteria. The evaluation was carried out by five experts and judged by majority vote. A: Visibility is such that the marked and unmarked areas can be distinguished visually. B: The visibility of the markings was poor when visually inspected.

[0141] [Table 3]

[0142] [Table 4]

[0143] [Table 5]

[0144] In Tables 3 to 5 above, "difference in SP value of resin" refers to the difference in absolute value between the SP value of PBT and the SP value of the resin used in the carbon black masterbatch (|SP 1 -SP 2 |). In Tables 3 to 5, the "amount of CB itself" refers to the amount of carbon black (parts by mass) per 100 parts by mass of the polyester resin and amorphous resin combined. In other words, it refers to the amount of carbon black itself, excluding the resin used in the masterbatch. As is clear from the above results, the molded articles molded from the resin composition of the present embodiment had high laser welding strength and were capable of being laser marked (Examples 1 and 2). In contrast, when the carbon black was not masterbatched with an amorphous resin or a thermoplastic resin satisfying a predetermined SP value (Comparative Example 1 and Comparative Examples 3 to 6), the laser weldability was poor, and the visibility of the laser-marked area was also poor. On the other hand, even when carbon black was masterbatched with an amorphous resin or a thermoplastic resin satisfying a predetermined SP value, when the amount of carbon black blended was high (Comparative Example 2), laser marking was possible, but laser weldability was poor. [Explanation of symbols]

[0145] 21 and 22 holes 23, 24 Jig for measuring adhesion strength 25, 26 Measuring jig

Claims

1. A resin composition comprising: more than 50 parts by mass but not more than 99.9 parts by mass of a polyester resin; and 0.1 parts by mass or more but not more than 50 parts by mass of an amorphous resin, for a total of 100 parts by mass of the polyester resin and 0.1 parts by mass or more but not more than 50 parts by mass of an amorphous resin; and 0.01 parts by mass or more but not more than 0.4 parts by mass of carbon black, wherein at least a portion of the amorphous resin is derived from a masterbatch of the carbon black.

2. The resin composition of claim 1 , wherein the polyester resin comprises a polybutylene terephthalate resin.

3. The SP value of the polyester resin (SP １ ) and the SP value of the amorphous resin (SP ２ ) absolute value of the difference (|SP １ -SP ２ The resin composition according to claim 1 or 2, wherein |) is 0 to 3.

0.

4. The resin composition according to claim 1 or 2, wherein the amorphous resin comprises a styrene-based resin.

5. The resin composition according to claim 1 or 2, wherein the amorphous resin comprises an acrylonitrile-styrene resin.

6. The resin composition according to claim 1 or 2, further comprising an elastomer.

7. The resin composition according to claim 1 or 2, which is used on the laser light absorbing side during laser welding.

8. The resin composition according to claim 1 or 2, which is used on the laser light absorbing side during laser welding and is for laser marking.

9. the polyester resin comprises a polybutylene terephthalate resin, the amorphous resin comprises an acrylonitrile-styrene resin, Further, it contains an elastomer, The resin composition according to claim 1, which is used on the laser light absorbing side during laser welding and is for laser marking.

10. The polyester resin contains 0.01 parts by mass or more and 0.4 parts by mass or less of carbon black relative to 100 parts by mass of a total of a polyester resin and a second thermoplastic resin other than the polyester resin, and at least a part of the second thermoplastic resin is derived from a master batch of the carbon black, and the SP value (SP １ ) and the SP value of the second thermoplastic resin (SP ２２ ) absolute value of the difference (|SP １ -SP ２２ |) is 0 to 3.

0.

11. the polyester resin comprises a polybutylene terephthalate resin, The resin composition according to claim 10, which is used on the laser light absorbing side during laser welding and is for laser marking.

12. A pellet of the resin composition according to any one of claims 1, 2, 9, 10 and 11.

13. A molded article formed from the resin composition according to any one of claims 1, 2, 9, 10 and 11.

14. A method for producing a resin composition, comprising adding and melt-kneading 0.01 part by mass or more and 0.4 part by mass or less of carbon black to a total of 100 parts by mass of more than 50 parts by mass but not more than 99.9 parts by mass of a polyester resin and 0.1 part by mass or more and 50 parts by mass or less of an amorphous resin, wherein at least a portion of the amorphous resin is added as a masterbatch of the carbon black.

15. The method according to claim 14, wherein the resin composition is the resin composition according to any one of claims 1, 2, 9, 10 and 11.

16. A kit comprising a laser-transmittable resin composition and the resin composition according to any one of claims 1, 2, 9, 10 and 11.

17. 12. A laser-welded article comprising a laser-transmitting resin workpiece formed from a laser-transmitting resin composition and a laser-absorbing resin workpiece formed from the resin composition according to claim 1.

18. Irradiating a laser onto a laser-absorbing resin member to perform laser marking; and The method for producing a laser-welded product according to claim 17, comprising laser welding a laser-transmitting resin member and the laser-absorbing resin member together.

19. The method for manufacturing a laser welded product according to claim 18, wherein the laser welding is performed by galvano scanning laser welding.

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