JP2023114412A - Resin composition, molded article, and laser welded body - Google Patents

Abstract

To provide a resin composition that can cope with a problem of an environmental load, the resin composition suitable for laser welding and/or laser marking, and a molded article and a laser welded body, each of which includes the resin composition.SOLUTION: This resin composition contains a polyester resin and a polycarbonate resin. A mass ratio of the polyester resin and the polycarbonate resin in a total of 100 pts.mass of the polyester resin and the polycarbonate resin is 10/90 to 90/10. The polycarbonate resin includes a recycled one. The polycarbonate resin has a molecular weight distribution (Mw/Mn) of 2.8 or more.SELECTED DRAWING: Figure 1

Description

TECHNICAL FIELD The present invention relates to a resin composition, a molded article, and a laser-welded article.

Thermoplastic polyester resins such as polybutylene terephthalate resin and polycarbonate resins are excellent in mechanical strength, heat resistance, moldability, and recyclability. widely used in

On the other hand, in recent years, there has been an increase in the number of cases where resin members made of thermoplastic resin are subjected to welding processing in order to improve productivity, and among them, laser welding, which has little effect on electronic parts, is frequently used ( For example, Patent Document 1).
In laser welding, a laser-transmitting resin member (hereinafter sometimes referred to as "transmitting resin member") made of a material that transmits laser light and a laser-absorbing resin member (hereinafter referred to as "absorbing resin member") made of a material that absorbs laser light. ), and a laser beam is irradiated from the transmissive resin member side to generate heat at the interface with the absorbing resin member for welding. A resin composition that is applied to a molded article for such use is required to have a performance (laser weldability) that enables welding by irradiation with a laser beam.

On the other hand, in many cases, product information is printed or drawn on the surface of the molded body from the viewpoint of designability at the time of completion, display of information, identification of parts at the time of assembly, and the like. And when they are required to maintain visibility over a long period of time, laser marking may be used from the viewpoint of reliability.
Furthermore, in recent years, a resin composition that can be used as a laser-transmitting resin member during laser welding and that is capable of being laser-marked has also been studied (Patent Document 2).

Japanese Patent No. 6183822 JP 2020-050822 A

As mentioned above, the demand for laser welding is increasing. Therefore, with the expansion of the use of such resins, new resin compositions with high laser transmittance are desired.
Further, in laser welding, a resin composition having high laser welding strength is also desired.
On the other hand, as described above, the demand for resins that can be laser-marked is also increasing, and with the expansion of the use of such resins, there is a demand for new resin compositions that are excellent in laser-markability.
Here, from the standpoint of the design of the laser-welded body, the transmissive resin member and the absorbing resin member are preferably colored in the same color. For example, the absorbing resin member and the transmissive resin member may be colored black. Here, if the transmissive resin member is colored with a pigment having a high absorptivity of laser light, like the absorptive resin member, the laser light will not be transmitted, making laser welding impossible. On the other hand, when performing laser marking on a transmissive resin member, marking cannot be performed if the laser beam is transmitted. Therefore, there is a demand for a resin composition that permits laser marking while transmitting laser light to some extent.
On the other hand, in recent years, from the viewpoint of environmental load, the use of recycled resins is being demanded.

Based on the above situation, the present invention provides a resin composition that is environmentally friendly and can be laser-welded and/or laser-marked, a molded article using the resin composition, and An object of the present invention is to provide a laser welded body.

Under the above-mentioned problems, the present inventors have investigated, and as a result, in a resin composition containing a polyester resin and a polycarbonate resin, by using a polycarbonate resin having a molecular weight distribution (Mw / Mn) of 2.8 or more, , it has been found that a resin composition capable of laser welding and/or laser marking is possible even when a recycled product is used as a polycarbonate resin.
Specifically, the above problems have been solved by the following means.
<1> including polyester resin and polycarbonate resin,
The mass ratio of the polyester resin and the polycarbonate resin in a total of 100 parts by mass of the polyester resin and the polycarbonate resin is 10/90 to 90/10,
The polycarbonate resin contains a recycled product,
The polycarbonate resin has a molecular weight distribution (Mw/Mn) of 2.8 or more.
Resin composition.
<2> The resin composition according to <1>, wherein the recycled product accounts for 50 parts by mass or more in 100 parts by mass of the polycarbonate resin.
<3> The resin composition according to <1> or <2>, wherein the polycarbonate resin has a viscosity-average molecular weight Mv of 20,000 or more.
<4> The resin composition according to any one of <1> to <3>, wherein the polyester resin contains a polybutylene terephthalate resin.
<5> The resin composition according to any one of <1> to <4>, further comprising an inorganic filler.
<6> The resin composition according to any one of <1> to <5>, further comprising a phosphorus stabilizer.
<7> The resin composition according to any one of <1> to <6>, which is for laser marking.
<8> The resin composition according to any one of <1> to <7>, which is used for a resin member transmitting laser light for laser welding.
<9> A molded article formed from the resin composition according to any one of <1> to <8>.
<10> The molded article according to <9>, which is for laser marking.
<11> A laser-welded article comprising the formed article according to <9> or <10>.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide a resin composition that is environmentally friendly and that can be laser-welded and/or laser-marked, a molded article using the resin composition, and a laser-welded article. Became.

1 is photographs of Example 1 and Comparative Examples 1 and 2 after laser printing. FIG. 2 is a schematic diagram showing a test piece (transmissive resin member I) for measuring laser welding strength in Examples. FIG. 2 is a schematic diagram showing a test piece (absorbing resin member II) for measuring laser welding strength in Examples. 1 is a schematic diagram showing a test piece (combination of transmitting resin member I and absorbing resin member II) for measuring laser welding strength in Examples. FIG. It is a schematic diagram showing a method of measuring the laser welding strength of the example.

EMBODIMENT OF THE INVENTION Hereinafter, the form (only henceforth "this embodiment") for implementing this invention is demonstrated in detail. In addition, the present embodiment below is an example for explaining the present invention, and the present invention is not limited only to the present embodiment.
In this specification, the term "~" is used to mean that the numerical values before and after it are included as the lower limit and the upper limit.
In this specification, various physical property values and characteristic values are at 23° C. unless otherwise specified.
If the measurement methods, etc. described in the standards shown in this specification differ from year to year, they shall be based on the standards as of January 1, 2022 unless otherwise stated.

The resin composition of the present embodiment contains a polyester resin and a polycarbonate resin, and the mass ratio of the polyester resin and the polycarbonate resin in a total of 100 parts by mass of the polyester resin and the polycarbonate resin is 10/90 to 90/10. The polycarbonate resin includes a recycled product, and the molecular weight distribution (Mw/Mn) of the polycarbonate resin is 2.8 or more.

With the above configuration, it is possible to provide a resin composition that is environmentally friendly and that can be laser-welded and/or laser-marked.
In particular, by adopting the above configuration, the compatibility between the polycarbonate resin and the polyester resin is improved, and a resin composition having a high transmittance can be provided. Moreover, since the laser transmittance is relatively improved by adopting the above structure, it can be suitably used as a laser-transmitting resin member at the time of laser welding. Furthermore, by adopting the above configuration, the compatibility between the polycarbonate resin and the polyester resin is improved, so that a resin composition having improved laser welding strength during laser welding can be obtained.
In particular, in the present embodiment, even if the recycled polycarbonate resin is used, the above performance is not hindered, so that a resin composition that is environmentally friendly while having the above performance can be obtained.

<Polyester resin>
The resin composition of this embodiment contains a polyester resin.
The type of the polyester resin used in the present embodiment is not particularly limited as long as it is a thermoplastic polyester resin. Polybutylene terephthalate resin and polyethylene terephthalate resin are exemplified, and polybutylene terephthalate resin is preferred.

<<Polybutylene terephthalate resin>>
Polybutylene terephthalate resin is a resin obtained by polycondensation of terephthalic acid as the main acid component and 1,4-butanediol as the main diol component. That the main component of the acid component is terephthalic acid means that 50% by mass or more of the acid component is terephthalic acid, preferably 60% by mass or more, more preferably 70% by mass or more, It may be 80% by mass or more, 90% by mass or more, or 95% by mass or more. 1,4-butanediol, which is the main component of the diol component, means that 50% by mass or more of the diol component is 1,4-butanediol, preferably 60% by mass or more, and 70% by mass. It is more preferably 80% by mass or more, 90% by mass or more, or 95% by mass or more.
Isophthalic acid and dimer acid are exemplified when the polybutylene terephthalate resin contains other acid components. Further, when the polybutylene terephthalate resin contains other diol components, polyalkylene glycol such as polytetramethylene glycol (PTMG) is exemplified.

When a copolymer of polytetramethylene glycol is used as the polybutylene terephthalate resin, the proportion of the tetramethylene glycol component in the copolymer is preferably 3 to 40% by mass, more preferably 5 to 30% by mass. Preferably, 10 to 25% by mass is more preferable. By setting such a copolymerization ratio, the balance between laser weldability and heat resistance tends to be excellent, which is preferable.

When dimer acid-copolymerized polybutylene terephthalate is used as the polybutylene terephthalate resin, the ratio of the dimer acid component to the total carboxylic acid component is preferably 0.5 to 30 mol % as carboxylic acid group, 20 mol % is more preferred, and 3 to 15 mol % is even more preferred. Such a copolymerization ratio tends to provide an excellent balance of laser weldability, long-term heat resistance, and toughness, which is preferable.

When isophthalic acid-copolymerized polybutylene terephthalate is used as the polybutylene terephthalate resin, the ratio of the isophthalic acid component to the total carboxylic acid component is preferably 1 to 30 mol %, more preferably 1 to 20 mol, in terms of carboxylic acid groups. %, more preferably 3 to 15 mol %. Such a copolymerization ratio tends to provide an excellent balance of laser weldability, heat resistance, injection moldability and toughness, which is preferable.

The polybutylene terephthalate resin used in the present embodiment is a resin (polybutylene terephthalate homopolymer) in which 90% by mass or more of the acid component is terephthalic acid and 90% by mass or more of the diol component is 1,4-butanediol, or , copolymerized polybutylene terephthalate resin obtained by copolymerizing polytetramethylene glycol, and isophthalic acid copolymerized polybutylene terephthalate resin are preferred.

The polybutylene terephthalate resin preferably has an intrinsic viscosity of 0.5 to 2 dL/g. From the standpoint of moldability and mechanical properties, those having an intrinsic viscosity in the range of 0.6 to 1.5 dL/g are more preferred. By using those having an intrinsic viscosity of 0.5 dL/g or more, the mechanical strength of the resulting molded article tends to be further improved. Further, by using a polybutylene terephthalate resin having an intrinsic viscosity of 2 dL/g or less, there is a tendency that the fluidity of the polybutylene terephthalate resin is improved, the moldability is improved, and the laser weldability is further improved.
The intrinsic viscosity is a value measured at 30° C. in a 1:1 (mass ratio) mixed solvent of tetrachloroethane and phenol.
When two or more polybutylene terephthalate resins are included, the intrinsic viscosity is the intrinsic viscosity of the mixture.

The amount of terminal carboxyl groups in the polybutylene terephthalate resin may be selected and determined as appropriate, but is usually 60 eq/ton or less, preferably 50 eq/ton or less, and more preferably 30 eq/ton or less. . By setting the amount of terminal carboxyl groups to 50 eq/ton or less, it is possible to more effectively suppress the generation of gas during melt molding of the polybutylene terephthalate resin. Although the lower limit of the amount of terminal carboxy groups is not particularly defined, it is usually 5 eq/ton.
When two or more polybutylene terephthalate resins are included, the amount of terminal carboxyl groups is the amount of terminal carboxyl groups in the mixture.

The terminal carboxy group content of the polybutylene terephthalate resin is obtained by dissolving 0.5 g of the polybutylene terephthalate resin in 25 mL of benzyl alcohol and titrating with a 0.01 mol/L benzyl alcohol solution of sodium hydroxide. is the value Examples of the method for adjusting the amount of terminal carboxyl groups include any conventionally known method, such as a method of adjusting polymerization conditions such as a raw material charge ratio during polymerization, polymerization temperature, and a decompression method, and a method of reacting a terminal blocking agent. be done.

<<Polyethylene terephthalate resin>>
The polyethylene terephthalate resin used in the present embodiment is a resin obtained by polycondensation of terephthalic acid as the main acid component and ethylene glycol as the main diol component. That the main component of the acid component is terephthalic acid means that 50% by mass or more of the acid component is terephthalic acid, preferably 60% by mass or more, more preferably 70% by mass or more, It may be 80% by mass or more, 90% by mass or more, or 95% by mass or more. The expression that the main component of the diol component is ethylene glycol means that 50% by mass or more of the diol component is ethylene glycol, preferably 60% by mass or more, more preferably 70% by mass or more. It may be 80% by mass or more, 90% by mass or more, or 95% by mass or more.

When the polyethylene terephthalate resin contains other acid components, phthalic acid, isophthalic acid, naphthalenedicarboxylic acid, 4,4'-diphenylsulfonedicarboxylic acid, 4,4'-biphenyldicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, 1 ,3-phenylenedioxydiacetic acid and structural isomers thereof, dicarboxylic acids such as malonic acid, succinic acid and adipic acid and derivatives thereof, oxy acids such as p-hydroxybenzoic acid and glycolic acid and derivatives thereof.
Further, when the polyethylene terephthalate resin contains other acid components, other diol components such as 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, pentamethylene glycol, hexamethylene glycol, neo Aliphatic glycols such as pentyl glycol, alicyclic glycols such as cyclohexanedimethanol, aromatic dihydroxy compound derivatives such as bisphenol A and bisphenol S, and the like.

Furthermore, the polyethylene terephthalate resin has a branching component, for example, a trifunctional acid such as tricarballylic acid, trimellitic acid, trimellitic acid, or a tetrafunctional acid such as pyromellitic acid, or an acid capable of forming an ester such as glycerin, trimethylolpropane, penta 1.0 mol % or less, preferably 0.5 mol % or less, more preferably 0.3 mol % or less of an alcohol having a trifunctional or tetrafunctional ester-forming ability such as erythritol is copolymerized. There may be.

The intrinsic viscosity of the polyethylene terephthalate resin is preferably 0.3 to 1.5 dL/g, more preferably 0.3 to 1.2 dL/g, still more preferably 0.4 to 0.8 dL/g. be.
The intrinsic viscosity of polyethylene terephthalate resin is a value measured at 30° C. in a 1:1 (mass ratio) mixed solvent of tetrachloroethane and phenol.

The terminal carboxy group concentration of the polyethylene terephthalate resin is preferably 3 to 60 eq/ton, more preferably 5 to 50 eq/ton, still more preferably 8 to 40 eq/ton. By setting the terminal carboxy group concentration to 60 eq/ton or less, gas is less likely to be generated during melt molding of the resin material, and the resulting molded product tends to have improved mechanical properties. /ton or more, the heat resistance, retention heat stability and hue of the resulting molded product tend to be improved, which is preferable.
The terminal carboxy group concentration of the polyethylene terephthalate resin is obtained by dissolving 0.5 g of polyethylene terephthalate resin in 25 mL of benzyl alcohol and titrating with a 0.01 mol/L benzyl alcohol solution of sodium hydroxide. value.

<Polycarbonate resin>
The resin composition of this embodiment contains a polycarbonate resin having a molecular weight distribution (Mw/Mn) of 2.8 or more.
Furthermore, in the resin composition of the present embodiment, the polycarbonate resin contains a recycled product. With such a configuration, a resin composition that is environmentally friendly can be obtained.

Recycled polycarbonate resins include those obtained by material recycling, in which collected used polycarbonate resin molded bodies are pulverized, washed with alkali, and reused as fibers, etc., those obtained by chemical recycling (chemical decomposition method), and mechanically recycled polycarbonate resins. Examples thereof include those obtained by recycling.
Chemical recycling involves chemically decomposing the collected used polycarbonate resin moldings to return them to the raw material level to resynthesize the polycarbonate resin. On the other hand, mechanical recycling is a method that makes it possible to remove stains from polycarbonate resin moldings more reliably than material recycling by performing more rigorous alkali washing in the material recycling described above or vacuum drying at high temperatures. is.
For example, a used polycarbonate resin molded article is pulverized, washed, and then pelletized by an extruder to obtain a recycled polycarbonate resin after removing foreign substances.

When the resin composition of the present embodiment contains recycled products, the content of recycled products is preferably 50 parts by mass or more, more preferably 55 parts by mass or more, based on 100 parts by mass of the polycarbonate resin. It is more preferably 60 parts by mass or more, still more preferably 70 parts by mass or more, even more preferably 80 parts by mass or more, and even more preferably 90 parts by mass or more. Recyclability improves by setting it as more than the said lower limit. Moreover, the upper limit of the content of the recycled product may be 100 parts by mass with respect to 100 parts by mass of the polycarbonate resin.

The molecular weight distribution (Mw/Mn) of the polycarbonate resin used in this embodiment is 2.8 or more. Such a configuration tends to further improve the laser transmittance and laser marking visibility of the resulting molded product. Also, laser welding strength tends to improve.
In the present embodiment, the molecular weight distribution (Mw/Mn) of the polycarbonate resin is preferably 2.9 or more, more preferably 3.0 or more, and even more preferably 3.1 or more. . Further, the molecular weight distribution (Mw/Mn) of the polycarbonate resin is preferably 5.0 or less, more preferably 4.0 or less, even more preferably 3.7 or less, and 3.5 It is more preferably 3.3 or less, and even more preferably 3.3 or less. By setting it as the said range, there exists a tendency for the effect of this embodiment to be exhibited more effectively.

The viscosity-average molecular weight Mv of the polycarbonate resin used in this embodiment is preferably 20,000 or more. When the content is equal to or higher than the above lower limit, the mechanical strength of the obtained molded article tends to be further improved. The viscosity-average molecular weight Mv of the polycarbonate resin is preferably 21,000 or more, more preferably 22,000 or more, still more preferably 23,000 or more, and 25,000 or more. More preferably, it is still more preferably 26,000 or more. Also, the viscosity average molecular weight (Mv) of the polycarbonate resin is preferably 60,000 or less, more preferably 40,000 or less, and even more preferably 30,000 or less. By using those having a molecular weight of 60,000 or less, the fluidity of the resin composition tends to be improved and the moldability tends to be improved.
When two or more polycarbonate resins are included, the mixture preferably satisfies the above range.

In the present embodiment, the viscosity average molecular weight (Mv) of the polycarbonate resin is obtained by measuring the viscosity of a methylene chloride solution of the polycarbonate resin at 20 ° C. using an Ubbelohde viscometer to obtain the intrinsic viscosity ([η]). , indicates a value calculated from the following Schnell viscosity equation.
[η]=1.23×10 ⁻⁴ Mv ^0.83

Polycarbonate resins are optionally branched homopolymers or copolymers obtained by reacting a dihydroxy compound or a small amount of a polyhydroxy compound with phosgene or a carbonic acid diester. The method for producing the polycarbonate resin is not particularly limited, and one produced by a conventionally known phosgene method (interfacial polymerization method) or melt method (ester exchange method) can be used, and the melt method is preferred. By using a polycarbonate resin obtained by a melting method, the polycarbonate resin has a branched structure, and the effects of the present invention tend to be exhibited more effectively.

The dihydroxy compound used as a raw material is preferably an aromatic dihydroxy compound, more preferably bisphenol, such as 2,2-bis(4-hydroxyphenyl)propane (=bisphenol A), tetramethylbisphenol A, bis(4-hydroxyphenyl)- p-diisopropylbenzene, hydroquinone, resorcinol, 4,4-dihydroxydiphenyl and the like are more preferred, and bisphenol A is even more preferred. A compound in which one or more tetraalkylphosphonium sulfonates are bonded to the above aromatic dihydroxy compound can also be used.

As the polycarbonate resin, among those mentioned above, an aromatic polycarbonate resin (bisphenol A type polycarbonate resin) derived from 2,2-bis(4-hydroxyphenyl)propane, or 2,2-bis(4-hydroxyphenyl) Aromatic polycarbonate copolymers derived from propane and other aromatic dihydroxy compounds are preferred. Alternatively, it may be a copolymer mainly composed of an aromatic polycarbonate resin, such as a copolymer with a polymer or oligomer having a siloxane structure. Furthermore, two or more of the above polycarbonate resins may be mixed and used.
In the present embodiment, a polycarbonate resin in which 90% by mass or more of the dihydroxy compound as a raw material monomer is 2,2-bis(4-hydroxyphenyl)propane is preferable, and 95% by mass or more is 2,2-bis(4-hydroxy A polycarbonate resin that is phenyl)propane is more preferred.

Monohydric aromatic hydroxy compounds may be used to control the molecular weight of polycarbonate resins, such as m- and p-methylphenol, m- and p-propylphenol, p-tert-butylphenol, p-long chain Alkyl-substituted phenols and the like can be mentioned.

The polycarbonate resin used in the present embodiment preferably has an aluminum element content of 0.50 to 1000.00 ppm by mass with respect to 100 parts by mass of the polycarbonate resin. By making it more than the said lower limit, there exists a tendency for laser marking property to improve more. When the content is equal to or less than the above upper limit, the long-term stability of the resin tends to be improved. The content of the aluminum element is more preferably 1.00 mass ppm or more, more preferably 1.20 mass ppm or more, and 2.00 mass ppm or more with respect to 100 mass parts of the polycarbonate resin. more preferably 3.00 mass ppm or more, and even more preferably 6.00 mass ppm or more. The content of the aluminum element is more preferably 500.00 mass ppm or less, more preferably 300.00 mass ppm or less, and 100.00 mass ppm or less with respect to 100 parts by mass of the polycarbonate resin. 10. is more preferably 50.00 mass ppm or less, even more preferably 30.00 mass ppm or less, even more preferably 15.00 mass ppm or less; 00 ppm by mass or less is particularly preferred.

In the present embodiment, the polycarbonate resin preferably contains calcium element in a proportion of 0.15 to 30.00 ppm by mass with respect to 100 parts by mass of the polycarbonate resin. The content of the calcium element is more preferably 0.50 mass ppm or more, more preferably 1.50 mass ppm or more, and 2.00 mass ppm or more with respect to 100 mass parts of the polycarbonate resin. more preferably 3.50 mass ppm or more, and even more preferably 4.00 mass ppm or more. By making it more than the said lower limit, there exists a tendency for laser marking property to improve more. The content of the calcium element is more preferably 30.00 mass ppm or less, more preferably 25.00 mass ppm or less, and 20.0 mass ppm or less with respect to 100 parts by mass of the polycarbonate resin. is more preferably 17.0 ppm by mass or less. By making the amount equal to or less than the upper limit, the long-term stability of the resin tends to be improved.

In this embodiment, the polycarbonate resin preferably contains 0.01 to 1.00 ppm by mass of strontium element with respect to 100 parts by mass of the polycarbonate resin. More preferably, the content of the strontium element is 0.02 ppm by mass or more with respect to 100 parts by mass of the polycarbonate resin. By making it more than the said lower limit, there exists a tendency for laser marking property to improve more. The content of the strontium element is more preferably 0.50 mass ppm or less, more preferably 0.10 mass ppm or less, and 0.09 mass ppm or less with respect to 100 mass parts of the polycarbonate resin. is more preferable, and 0.08 ppm by mass or less is even more preferable. When the content is equal to or less than the above upper limit, the long-term stability of the resin tends to be improved.

In the present embodiment, the polycarbonate resin preferably contains barium element at a rate of 0.09 to 10.00 ppm by mass with respect to 100 parts by mass of the polycarbonate resin. The content of the barium element is more preferably 0.10 mass ppm or more, more preferably 0.13 mass ppm or more, and 0.15 mass ppm or more with respect to 100 parts by mass of the polycarbonate resin. more preferably 0.18 mass ppm or more, and even more preferably 0.20 mass ppm or more. By making it more than the said lower limit, there exists a tendency for laser marking property to improve more. The content of the barium element is more preferably 7.00 mass ppm or less, more preferably 3.00 mass ppm or less, and 1.50 mass ppm or less with respect to 100 parts by mass of the polycarbonate resin. is more preferable, and it is even more preferable that it is 1.00 ppm by mass or less. By making the amount equal to or less than the upper limit, the long-term stability of the resin tends to be improved.

In the present embodiment, the polycarbonate resin preferably contains magnesium element in a proportion of 0.08 to 20.00 ppm by mass with respect to 100 parts by mass of the polycarbonate resin. The content of the magnesium element is more preferably 0.10 mass ppm or more, more preferably 0.15 mass ppm or more, and 0.50 mass ppm or more with respect to 100 mass parts of the polycarbonate resin. more preferably 0.70 mass ppm or more, and even more preferably 1.00 mass ppm or more. By making it more than the said lower limit, there exists a tendency for laser marking property to improve more. The content of the magnesium element is more preferably 30.00 mass ppm or less, more preferably 20.00 mass ppm or less, and 10.00 mass ppm or less with respect to 100 parts by mass of the polycarbonate resin. is more preferable, and it is even more preferable that it is 8.00 mass ppm or less. When the content is equal to or less than the above upper limit, the long-term stability of the resin tends to be improved.

In the present embodiment, the polycarbonate resin preferably contains zinc element in a proportion of 0.05 to 10.00 ppm by mass with respect to 100 parts by mass of the polycarbonate resin. The zinc element content is more preferably 0.08 ppm by mass or more, and even more preferably 0.10 ppm by mass or more, relative to 100 parts by mass of the polycarbonate resin. By making it more than the said lower limit, there exists a tendency for laser marking property to improve more. The content of the zinc element is more preferably 7.00 mass ppm or less, more preferably 3.00 mass ppm or less, and 2.00 mass ppm or less with respect to 100 parts by mass of the polycarbonate resin. is more preferable, and it is even more preferable that it is 1.00 ppm by mass or less. When the content is equal to or less than the above upper limit, the long-term stability of the resin tends to be improved.

In the present embodiment, the polycarbonate resin preferably contains iron elements in a proportion of 0.35 to 50.0 ppm by mass with respect to 100 parts by mass of the polycarbonate resin. The content of the iron element is more preferably 0.80 mass ppm or more, more preferably 1.00 mass ppm or more, and 2.00 mass ppm or more with respect to 100 mass parts of the polycarbonate resin. more preferably 3.00 mass ppm or more, and even more preferably 5.00 mass ppm or more. By making it more than the said lower limit, there exists a tendency for laser marking property to improve more. The content of the iron element is more preferably 35.00 mass ppm or less, more preferably 20.00 mass ppm or less, and 15.00 mass ppm or less with respect to 100 parts by mass of the polycarbonate resin. is more preferably 10.00 ppm by mass or less. By making the amount equal to or less than the upper limit, the long-term stability of the resin tends to be improved.

In the present embodiment, the polycarbonate resin preferably contains manganese element in a proportion of 0.07 to 10.00 ppm by mass with respect to 100 parts by mass of the polycarbonate resin. More preferably, the manganese element content is 0.08 ppm by mass or more relative to 100 parts by mass of the polycarbonate resin. By making it more than the said lower limit, there exists a tendency for laser marking property to improve more. The content of the manganese element is more preferably 7.00 mass ppm or less, more preferably 3.00 mass ppm or less, and 1.00 mass ppm or less with respect to 100 parts by mass of the polycarbonate resin. more preferably 0.50 ppm by mass or less, and even more preferably 0.20 ppm by mass or less. When the content is equal to or less than the above upper limit, the long-term stability of the resin tends to be improved.

In the present embodiment, the polycarbonate resin preferably contains at least aluminum element and iron element, respectively, within the above ranges.

In addition, the metal element does not necessarily exist as a single element in the polycarbonate resin, and may be included as a part of the compound. In the present embodiment, the measured value of <measurement of the amount of metal element> described in Examples described later is used as the amount of the metal element.

In accordance with ISO 1133 for polycarbonate resin, the melt volume rate (MVR) at a measurement temperature of 300°C and a measurement load of 1.20 kgf is preferably 1 cm ³ /10 min or more, more preferably 2 cm ³ /10 min or more. More preferably, it is 3 cm ³ /10 minutes or more, and even more preferably 4 cm ³ /10 minutes or more. When the amount is at least the above lower limit, the fluidity of the resin tends to be improved during injection molding. The upper limit of the MVR is preferably 13 cm ³ /10 min or less, more preferably 12 cm ³ /10 min or less, even more preferably 11 cm ³ /10 min or less, and 10 cm ³ /10 min. Minutes or less is more preferable, and 9 cm ³ /10 minutes or less is even more preferable. The mechanical strength tends to be improved by making it equal to or less than the above upper limit.

<Mass ratio of polyester resin and polycarbonate resin>
Next, the ratio of the polyester resin and the polycarbonate resin in the resin composition of this embodiment will be described.
In the resin composition of the present embodiment, the mass ratio of the polyester resin and the polycarbonate resin in a total of 100 parts by mass of the polyester resin and the polycarbonate resin is 10/90 to 90/10, and 20/80 to 90/10. preferably 30/70 to 90/10, more preferably 40/60 to 90/10, even more preferably 50/50 to 90/10, and 50/50 80/20 is even more preferred, 50/50 to 70/30 is even more preferred, 55/45 to 70/30 is even more preferred, and 55/45 to 65/35 is even more preferred. One is more particularly preferred.

In the resin composition of the present embodiment, the total of the polyester resin and the polycarbonate resin preferably accounts for 80% by mass or more of the resin components contained in the resin composition, more preferably 85% by mass or more, and 90% by mass. % or more, more preferably 95 mass % or more, and even more preferably 98 mass % or more.
Furthermore, in the resin composition of the present embodiment, the total of the polyester resin and the polycarbonate resin preferably accounts for 55% by mass or more of the resin composition, more preferably 60% by mass or more, and 65% by mass or more. More preferably, it accounts for 68% by mass or more. Moreover, the total amount of the polyester resin and the polycarbonate resin in the resin composition is preferably 80% by mass or less, more preferably 75% by mass or less.
The resin composition of the present embodiment may contain only one kind of each of the polyester resin and the polycarbonate resin, or may contain two or more kinds thereof. When two or more types are included, the total amount is preferably within the above range.

<Inorganic filler>
Preferably, the resin composition of the present embodiment further contains an inorganic filler. Inorganic fillers, preferably fibrous or scaly inorganic fillers, more preferably glass fibers and/or glass flakes, improve the mechanical strength, heat resistance, and durability of the laser welded product. tend to improve.

The inorganic filler that can be contained in the resin composition of the present embodiment has the effect of improving the mechanical properties of the resin composition obtained by being blended in the resin, and is a commonly used inorganic filler for plastics. can be used. Preferably fibrous inorganic fillers such as glass fiber, carbon fiber, basalt fiber, wollastonite and potassium titanate fiber can be used. Granular or amorphous fillers such as calcium carbonate, titanium oxide, feldspar minerals, clay, organic clay, and glass beads; plate-like fillers such as talc; scaly fillers such as glass flakes, mica, and graphite. Inorganic fillers can also be used. Among them, from the viewpoint of mechanical strength, rigidity and heat resistance, it is preferable to contain glass fiber and/or glass flakes, and it is particularly preferable to use glass fiber. As the glass fiber, either a round cross-sectional shape or an irregular cross-sectional shape can be used.
The inorganic filler is more preferably surface-treated with a surface-treating agent such as a coupling agent. A glass fiber to which a surface treatment agent is adhered is preferable because it is excellent in durability, wet heat resistance, hydrolysis resistance, and heat shock resistance.

As the surface treatment agent, any conventionally known one can be used, and specifically, silane coupling agents such as aminosilane-based, epoxysilane-based, allylsilane-based, and vinylsilane-based agents are preferred. Among these, aminosilane-based surface treatment agents are preferred, and specifically, γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane and γ-(2-aminoethyl)aminopropyltrimethoxysilane are preferred. Examples include:

As other surface treatment agents, epoxy resin surface treatment agents such as novolak type, bisphenol A type epoxy resin surface treatment agents and the like are also preferable, and treatment with novolak type epoxy resin surface treatment agents is particularly preferable.
The silane-based surface treating agent and the epoxy resin-based surface treating agent may be used singly or in combination, and it is also preferable to use both together. The glass fiber in the present embodiment means a fibrous glass material, more specifically, a chopped shape obtained by bundling 1,000 to 10,000 glass fibers and cutting them to a predetermined length. preferable.
The glass fiber in the present embodiment preferably has a number average fiber length of 0.5 to 10 mm, more preferably 1 to 5 mm. By using glass fibers having such a number average fiber length, the mechanical strength can be further improved. The number average fiber length is obtained by randomly extracting the glass fibers whose fiber length is to be measured from the image obtained by observation with an optical microscope, measuring the long side, and calculating the number average fiber length from the obtained measured value. calculate. The magnification of observation is 20 times, and the number of lines to be measured is 1,000 or more. It roughly corresponds to the cut length.
The cross-section of the glass fiber may be circular, elliptical, oval, rectangular, semicircular on both short sides of a rectangle, cocoon-shaped, etc., but circular is preferred. The circle here is intended to include what is usually called a circle in the technical field of the present embodiment in addition to the geometric meaning of the circle.
The lower limit of the number average fiber diameter of the glass fibers is preferably 4.0 μm or more, more preferably 4.5 μm or more, and even more preferably 5.0 μm or more. The upper limit of the number average fiber diameter of the glass fibers is preferably 15.0 μm or less, more preferably 14.0 μm or less. By using glass fibers having a number-average fiber diameter within such a range, there is a tendency to obtain a molded article having more excellent mechanical strength. The number average fiber diameter of the glass fiber is obtained by randomly extracting the glass fiber whose fiber diameter is to be measured from the image obtained by observation with an electron microscope, and measuring the fiber diameter near the center. calculated from the measured values obtained. The magnification of observation is 1,000, and the number of lines to be measured is 1,000 or more. The number average fiber diameter of glass fibers having a non-circular cross section is the number average fiber diameter when converted to a circle having the same area as the cross section.

Glass fibers are commonly supplied E glass (Electrical glass), C glass (Chemical glass), A glass (Alkali glass), S glass (High strength glass), D glass, R glass and alkali resistant glass. Fibers obtained by melt-spinning glass are used, but there is no particular limitation as long as they can be made into glass fibers. In this embodiment, it is preferable to include E-glass.

The glass fibers used in this embodiment are treated with a surface treatment agent such as a silane coupling agent such as γ-methacryloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-aminopropyltriethoxysilane. It is preferably treated. The adhesion amount of the surface treatment agent is preferably 0.01 to 1 mass % of the glass fiber. Furthermore, if necessary, lubricants such as fatty acid amide compounds, silicone oils, antistatic agents such as quaternary ammonium salts, resins having film-forming properties such as epoxy resins and urethane resins, resins having film-forming properties and heat It is also possible to use those surface-treated with a mixture of stabilizers, flame retardants, and the like.

Glass fibers are commercially available. Commercially available products include T-286H, T-756H, T-127, T-289H manufactured by Nippon Electric Glass Co., Ltd., DEFT2A manufactured by Owens Corning, HP3540 manufactured by PPG, and CSG3PA820 manufactured by Nittobo. are mentioned.

The content of the inorganic filler (preferably glass fiber) in the resin composition of the present embodiment is preferably 10 parts by mass or more with respect to 100 parts by mass of the thermoplastic resin (the total of the polyester resin and the polycarbonate resin). It is more preferably 15 parts by mass or more, still more preferably 20 parts by mass or more, still more preferably 25 parts by mass or more, and even more preferably 30 parts by mass or more. When the content is at least the above lower limit, the strength of the base material of the laser-welded body tends to increase, and the heat resistance of the laser-welded body tends to increase. Further, the upper limit of the content of the inorganic filler is preferably 70 parts by mass or less, more preferably 60 parts by mass or less, and 50 parts by mass or less with respect to 100 parts by mass of the thermoplastic resin. is more preferred. By making it equal to or less than the above upper limit, there is a tendency for the welding strength at the interface to increase.

In addition, the content of the inorganic filler (preferably glass fiber) in the resin composition of the present embodiment is preferably 20% by mass or more, more preferably 25% by mass or more. In addition, the content of the inorganic filler (preferably glass fiber) is preferably 45% by mass or less, more preferably 40% by mass or less, and more preferably 35% by mass or less. % by mass or less is more preferable.
The resin composition of the present embodiment may contain only one type of inorganic filler (preferably glass fiber), or may contain two or more types. When two or more types are included, the total amount is preferably within the above range.

<Stabilizer>
The resin composition of the present embodiment preferably contains a stabilizer, and the stabilizer is preferably a phosphorus-based stabilizer or a phenol-based stabilizer, and more preferably a phosphorus-based stabilizer. By containing the phosphorus stabilizer, deterioration of the resin during processing and in a high temperature environment can be suppressed.

Any known phosphorus stabilizer can be used. Specific examples include phosphorus oxo acids such as phosphoric acid, phosphonic acid, phosphorous acid, phosphinic acid, and polyphosphoric acid; acid pyrophosphate metal salts such as sodium acid pyrophosphate, potassium acid pyrophosphate, and calcium acid pyrophosphate; phosphoric acid; phosphates of group 1 or group 2 metals such as potassium, sodium phosphate, cesium phosphate, zinc phosphate; Especially preferred.
Examples of phenol-based stabilizers include hindered phenol-based antioxidants.
These details can be referred to paragraphs 0105 to 0111 of WO2020/013127, the contents of which are incorporated herein.

The content of the stabilizer is usually 0.001 parts by mass or more, preferably 0.01 parts by mass or more, and usually 2 parts by mass or less, preferably It is 1.0 parts by mass or less. By making the content of the stabilizer equal to or higher than the lower limit of the above range, the effect of the stabilizer can be obtained more effectively. Moreover, by setting the content of the stabilizer to the upper limit value or less of the above range, the effect does not reach a ceiling and it is economical.
The resin composition of the present embodiment may contain only one stabilizer, or may contain two or more stabilizers. When two or more types are included, the total amount is preferably within the above range.

<Release agent>
The resin composition of this embodiment may contain a release agent. Examples of the release agent include montan acid ester wax, polyolefin wax, higher fatty acids, ester compounds, ethylene bis stearamide, etc. At least one selected from montan acid ester wax, polyolefin wax and ethylene bis stearamide is used. preferable.
As the release agent, specifically, the description of paragraphs 0063 to 0077 of JP-A-2018-070722 and the description of paragraphs 0090-0098 of JP-A-2019-123809 can be referred to, and the contents of these are described in the present specification. incorporated into the book.

When the resin composition of the present embodiment contains a release agent, the content thereof is preferably 0.01 parts by mass or more, and 0.08 parts by mass with respect to the total 100 parts by mass of the polyester resin and the polycarbonate resin. It is more preferable to be above. In addition, the upper limit of the content of the release agent is preferably 5.0 parts by mass or less, more preferably 1.0 parts by mass or less, with respect to a total of 100 parts by mass of the polyester resin and the polycarbonate resin. preferable.
The resin composition of the present embodiment may contain only one release agent, or may contain two or more release agents. When two or more types are included, the total amount is preferably within the above range.

<Colorant>
The resin composition of this embodiment may contain a coloring agent (dye and/or pigment). By including a coloring agent, the design of the resulting molded article can be enhanced. The colorant may be either a dye or a pigment, but a dye is preferred.
The dye used in this embodiment is preferably a black dye and/or a black dye composition. A black dye composition means a dye composition that exhibits a black color by combining two or more kinds of chromatic dyes such as red, blue and green. A first embodiment of the black dye composition is a form containing a green dye and a red dye. A second embodiment of the black dye composition is a form containing a red dye, a blue dye and a yellow dye.
When the resin composition of the present embodiment is used as a light-transmitting resin composition for laser welding, the colorant (preferably dye) is a light-transmitting pigment. The light-transmitting dye includes, for example, polybutylene terephthalate resin (eg, Novaduran (registered trademark) 5008), glass fiber (eg, manufactured by Nippon Electric Glass Co., Ltd., trade name: T-127) 30% by mass, and a dye ( A dye considered to be a light-transmitting dye) 0.2% by mass is blended so that the total is 100% by mass, and the light transmittance measured by the method described in paragraph 0105 of WO 2021/225154 is 20.0. % or more. Specific examples of light-transmitting dyes include phthalocyanine, aniline black, phthalocyanine, porphyrin, perinone, quaterrylene, azo, azomethine, anthraquinone, pyrazolone, squaric acid derivative, perylene, chromium complex, and immonium. Anthraquinone and perinone are preferred, and anthraquinone and perinone are more preferred.
Furthermore, by blending the light-transmitting dye in this embodiment, for example, when the resin composition of this embodiment is molded to a thickness of 1.5 mm, the light transmittance at a wavelength of 1064 nm is 20.0% or more. Furthermore, it can be 40.0% or more, particularly 50.0% or more, or 60.0% or more. Although the upper limit is ideally 100%, it may be 90% or less.
A wavelength of 1064 nm is an example of the wavelength of a laser used for laser welding, and a laser transmittance of 20% or more at this wavelength means that laser welding can be performed satisfactorily.

Commercially available light-transmitting dyes include Colorants Plast Yellow 8000, Plast Red M 8315, and Plast Red 8370 manufactured by Arimoto Kagaku Co., Ltd., and Colorants Macrolex Yellow 3G and Macrolex manufactured by LANXESS. Examples thereof include Red EG, Macrolex Green 5B, KP Plastic HK, KP Plastic Red HG, KP Plastic Red H2G, KP Plastic Blue R, KP Plastic Blue GR, and KP Plastic Green G manufactured by Kiwa Kagaku Kogyo Co., Ltd.
In addition, dyes described in Japanese Patent No. 4157300 and dyes described in Japanese Patent No. 4040460 can also be employed, the contents of which are incorporated herein.

Pigments used in the present embodiment include inorganic pigments (carbon black (e.g., acetylene black, lamp black, thermal black, furnace black, channel black, ketjen black, etc.) and other black pigments, iron oxide red and other red pigments, molybdate orange pigments such as oranges, white pigments such as titanium oxide), organic pigments (yellow pigments, orange pigments, red pigments, blue pigments, green pigments, etc.), and the like. Black pigments are preferred, and carbon black is more preferred.
When the resin composition of the present embodiment contains a pigment, it is preferably used in masterbatch form with a thermoplastic resin (preferably a polyester resin, more preferably a polybutylene terephthalate resin). The pigment concentration in the masterbatch is preferably 1 to 50% by mass.

When the resin composition of the present embodiment contains a colorant, the content thereof is preferably 0.01 parts by mass or more, and 0.05 parts by mass or more with respect to a total of 100 parts by mass of the polyester resin and the polycarbonate resin. and more preferably 0.1 parts by mass or more. By making it more than the said lower limit, the coloring effect is exhibited more effectively. In addition, the upper limit of the content of the colorant is preferably 4 parts by mass or less, more preferably 3 parts by mass or less, and 2 parts by mass with respect to a total of 100 parts by mass of the polyester resin and the polycarbonate resin. It is more preferably 1 part by mass or less, and even more preferably 1 part by mass or less. When the content is equal to or less than the above upper limit, the mechanical strength of the molded article to be obtained tends to be further improved.
The resin composition of the present embodiment may contain only one colorant, or may contain two or more colorants. When two or more types are included, the total amount is preferably within the above range.

<Other ingredients>
The resin composition of the present embodiment may optionally contain other components in addition to those mentioned above, as long as the desired physical properties are not significantly impaired. Examples of other components include various resin additives. In addition, 1 type may be contained and 2 or more types may contain other components by arbitrary combinations and a ratio.
Specific examples of resin additives include reactive compounds, nucleating agents, flame retardants, flame retardant aids, fillers, antistatic agents, antifog agents, fluidity improvers, plasticizers, dispersants, and antibacterial agents. etc.
In the resin composition of the present embodiment, the total of polyester resin, polycarbonate resin and inorganic filler (preferably glass fiber) preferably accounts for 95% by mass or more of the resin composition, more preferably 98% by mass or more. preferable.

<Method for producing resin composition>
The resin composition of the present embodiment can be produced by a conventional method for preparing resin compositions. Generally, each component and optional additives are thoroughly mixed together and then melt-kneaded in a single-screw or twin-screw extruder. The resin composition of the present embodiment can also be prepared by not premixing the respective components or premixing only a part of them, supplying the components to an extruder using a feeder, and melt-kneading them. Some components such as a colorant may be melt-kneaded with a thermoplastic resin to prepare a masterbatch, and then the remaining components may be blended and melt-kneaded.
When using an inorganic filler, it is also preferable to supply it from a side feeder in the middle of the cylinder of the extruder.
The heating temperature for melt-kneading can be appropriately selected from the range of 220 to 300°C. If the temperature is too high, decomposition gas is likely to be generated, which may cause opacification. Therefore, it is desirable to select a screw structure in consideration of shear heat generation and the like. In order to suppress decomposition during kneading and subsequent molding, it is desirable to use antioxidants and heat stabilizers.

<Molded article and method for producing molded article>
The resin composition of this embodiment is molded according to a known method. That is, the molded article of this embodiment is formed from the resin composition of this embodiment.
The method for producing the molded article is not particularly limited, and any molding method generally employed for polyester resin compositions can be employed. Examples include injection molding, ultra-high speed injection molding, injection compression molding, two-color molding, hollow molding such as gas assist, molding using heat insulating molds, and rapid heating molds. Molding method, foam molding (including supercritical fluid), insert molding, IMC (in-mold coating molding) molding method, extrusion molding method, sheet molding method, thermoforming method, rotational molding method, laminate molding method, press molding method, A blow molding method and the like can be mentioned, and injection molding is particularly preferable.
Details of injection molding can be referred to paragraphs 0113 to 0116 of Japanese Patent No. 6183822, the contents of which are incorporated herein.

<Laser marking method>
A molded article formed from the resin composition of the present embodiment can be a resin composition capable of laser marking. That is, the resin composition or molded article of this embodiment is preferably used for laser marking.
Letters, signs, bar codes, QR codes (registered trademarks), drawings, patterns, etc. can be applied to molded articles by laser marking. Known methods can be widely adopted for the laser marking method.
A laser beam of 500 nm or more is more preferable as the laser beam used in the laser marking method. Further, the upper limit of the laser oscillation wavelength is more preferably 1200 nm or less.
Specifically, laser markers with wavelengths of 1,064 nm, 1090 nm, 1060 nm, and the like are used in applications for colored printing on molded articles. A crystal such as neodymium-modified yttrium-aluminum-garnet (YAG) or neodymium-modified yttrium-vanadium tetroxide (Nd:YVO ₄ ) is irradiated with high-power light to generate a laser, which is amplified by reciprocating reflection of a mirror. A laser marker that uses a Q-switch device to generate a pulsed laser can also be used. In addition, it is also possible to use a laser marker that uses multiple laser diodes (LD) at low output in a fiber injected with ytterbium, which is becoming mainstream in recent years, to generate and amplify laser light. can be done. A green laser marker with a wavelength of 532 nm can also be used.

As for the laser marker, the laser beam may be single mode or multimode, and in addition to narrow beam diameters of 20 to 40 μm, wide beam diameters of 80 to 100 μm can also be used. However, a single mode with a beam diameter of 20 to 40 μm is preferable because marking can be performed with good contrast.

<Laser welding>
The resin composition of the present embodiment can be used as a kit for laser welding in combination with a light-absorbing resin composition. That is, the resin composition of the present embodiment serves as a light-transmitting resin composition, and a molded article formed from such a light-transmitting resin composition is used as a resin member that transmits laser light during laser welding. can be used. The transmissive resin member can be used as a laser-welded body by laser welding with a molded body (a resin member that absorbs laser light during laser welding) formed from a light-absorbing resin composition. Here, the light-absorbing resin composition contains a thermoplastic resin and a light-absorbing pigment (for example, carbon black). Furthermore, it may contain an inorganic filler.
Since the resin composition of the present embodiment can be laser-marked when formed into a molded article, it can be laser-marked and is preferably used as a resin composition for transparent resin members in laser welding.

Details of the laser welding method and the light-absorbing resin composition can be referred to in paragraphs 0083 to 0092 of International Publication No. 2021/225154, the contents of which are incorporated herein.

The laser light source used for laser welding can be determined according to the light absorption wavelength of the light-absorbing dye, and a laser with a wavelength of 800 to 1100 nm is preferable. Examples of the type of laser light to be irradiated include solid lasers, fiber lasers, semiconductor lasers, gas lasers, liquid lasers, and the like. For example, YAG (yttrium aluminum garnet crystal) laser (wavelength 1064 nm, 1070 nm), LD (laser diode) laser (wavelength 808 nm, 840 nm, 940 nm, 980 nm), etc. can be preferably used. Among them, laser beams with wavelengths of 940 nm, 980 nm and 1070 nm are preferable.

<Application>
The resin composition or molded article of the present embodiment can be used in various applications, specifically, various storage containers, electrical and electronic equipment parts, office automation (OA) equipment parts, home appliance parts, mechanical mechanism parts, vehicle mechanisms. It can be applied to parts and the like. In particular, food containers, chemical containers, oil product containers, vehicle hollow parts (various tanks, intake manifold parts, camera housings), vehicle electrical components (various control units, ignition coil parts, etc.), motor parts, etc. It can be suitably used for sensor parts, connector parts, switch parts, breaker parts, relay parts, coil parts, transformer parts, lamp parts and the like.

In particular, the laser-welded body of this embodiment is preferably used for vehicle-mounted camera parts, sensor case parts, motor parts, and electronic control parts. More specifically, in-vehicle camera parts and in-vehicle camera modules including in-vehicle camera parts, millimeter wave radar housings, ECU case housings, sensor case housings such as sonar sensors, motor parts such as electric parking brakes, etc. Suitable for enclosures.

EXAMPLES The present invention will be described more specifically with reference to examples below. The materials, usage amounts, ratios, processing details, processing procedures, etc. shown in the following examples can be changed as appropriate without departing from the gist of the present invention. Accordingly, the scope of the present invention is not limited to the specific examples shown below.
If the measuring instruments and the like used in the examples are discontinued and difficult to obtain, other instruments having equivalent performance can be used for measurement.

1. Raw Materials The following raw materials were used. PBT is an abbreviation for polybutylene terephthalate resin.

<Measurement of Weight Average Molecular Weight (Mw) and Number Average Molecular Weight (Mn)>
The molecular weight was measured using HLC-8320GPC/EcoSEC (manufactured by TOSOH). The measurement conditions are as follows.
Column: Shodex KF-G + KF-805L x 3 + KF-800D
Detector: UV detector 254 nm
Column temperature: 40°C
Eluent: Tetrahydrofuran (THF)

「＜」は検出限界未満であることをいう。 The amounts of metal elements in 100 parts by mass of various polycarbonate resins in Table 1 are shown below. The unit of metal element is mass ppm.

“<” means less than detection limit.

<Measurement of amount of metal element>
Qualitative/semi-quantitative analysis of metal elements in the polycarbonate resin was performed by ICP emission spectrometry. In this case, 200 mg of the sample is weighed as a pretreatment, Kjeldahl wet decomposition (sulfuric acid/nitric acid, sulfuric acid/hydrogen peroxide) is performed, the volume is adjusted to 50 mL, and then ICP emission spectrometry is performed by the acid concentration matching single point calibration method. went. The unit is mass ppm.
ICP emission spectrometry was performed by axial/radial photometry using "iCAP76000uo" manufactured by Thermo Fisher Scientific.

2. Examples 1 and 2, Comparative Examples 1-3
<Compound>
Each component shown in Table 1 was uniformly mixed with a tumbler mixer at a ratio (parts by mass) shown in Table 3 with components other than the glass fiber. The obtained mixture was supplied to a twin-screw extruder (“TEX30α” manufactured by Japan Steel Works, Ltd.) from the main feed port. The cylinder set temperature of the first kneading section was set to 260° C., and glass fibers were supplied from a side feeder. After adding the glass fiber, the cylinder temperature was set to 240° C., and the resin composition melted and kneaded under the conditions of a discharge rate of 40 kg/h and a screw rotation speed of 200 rpm was rapidly cooled in a water tank and pelletized using a pelletizer to obtain a resin composition. of pellets were obtained.

<Light transmittance>
After drying the pellets obtained above at 120 ° C. for 5 hours, a plate-shaped molded body of 60 mm square and 1.5 mm thick was molded using an injection molding machine ("NEX80" manufactured by Nissei Plastic Industry Co., Ltd.) at a cylinder temperature of 260 ° C. and a mold temperature of 80°C. The obtained plate was measured for 1064 nm light transmittance (unit: %) at a point 45 mm from the gate and at the center of the width of the test plate using an ultraviolet-visible spectrophotometer.
As a UV-visible spectrophotometer, an integrating sphere-equipped "UV-3100PC" manufactured by Shimadzu Corporation was used.

<Environmental load>
It was evaluated as follows.
A: When using recycled polycarbonate resin does not adversely affect other performance (including cases where other performance is improved)
B: Other than above A (when only virgin polycarbonate resin is used, when recycled polycarbonate resin is used, other performance is adversely affected, etc.)

<Laser marking visibility>
After drying the pellets obtained above at 120 ° C. for 5 hours, a plate-shaped molded body of 60 mm square and 1.5 mm thick was molded using an injection molding machine ("NEX80" manufactured by Nissei Plastic Industry Co., Ltd.) at a cylinder temperature of 260 ° C. and a mold temperature of 80°C. Using a laser marking device (“LP-Z130” manufactured by Panasonic Devices SUNX Co., Ltd.) on the surface of the obtained plate molding, laser marking is performed under the conditions of a scan speed of 200 mm / s, a printing pulse period of 50 μs, and a line width of 0.1 mm. was performed, and the visibility of the laser-marked portion was visually evaluated as follows. The measurement was performed by five experts and judged by a majority vote.
A: The boundary between the printed part and the non-printed part is clear and there is no bleeding.
B: There is a lot of bleeding, and it is difficult to distinguish the boundary between the printed portion and the non-printed portion.
Photographs of Example 1 and Comparative Examples 1 and 2 after laser printing are shown in FIG. In Example 1, the boundary between the printed portion and the non-printed portion was clear, there was no bleeding, and clear laser printing was performed. On the other hand, in Comparative Examples 1 and 2, there was much blurring, it was difficult to distinguish the boundary between the printed portion and the non-printed portion, and the accuracy of the laser printability was inferior.

<Tensile strength and tensile modulus>
After drying the resin pellets obtained above at 120 ° C. for 5 hours, an ISO multi-purpose test piece (thickness 4 mm) was molded using an injection molding machine (“J85AD” manufactured by Japan Steel Works, Ltd.) at a cylinder temperature of 250 ° C. Injection molding was performed at a mold temperature of 80°C.
Using molded multi-purpose ISO multi-purpose test pieces, tensile strength (unit: MPa) and tensile modulus (unit: MPa) were measured according to ISO527-1 and ISO527-2.

The resin composition of the present invention had a high laser transmittance. Therefore, it turned out that it is suitable for laser welding. Furthermore, preliminary tests by the inventors revealed that the laser welding strength was also high.
The resin composition of the present invention does not adversely affect various performances even when the recycled polycarbonate resin is used, and is environmentally friendly.
The resin composition of the present embodiment had high laser print visibility. That is, it had excellent laser marking properties.
Furthermore, since the resin composition of the present embodiment has high laser transmittance and excellent laser marking properties, it is suitably used as a resin composition capable of laser welding and/or laser marking.

Laser welding <Forming of the first member>
After drying the resin pellets at 120 ° C. for 5 hours, they were molded at a cylinder temperature of 260 ° C. and a mold temperature of 60 ° C. using an injection molding machine (“J55” manufactured by Japan Steel Works, Ltd.), as shown in FIG. A molded body (transparent resin member I) having a thickness of 1.5 mm was produced.

<Molding of the second member>
After drying PBT resin (NOVADURAN 5010G30X4/BK2) manufactured by Mitsubishi Engineering-Plastics Corporation for 5 hours at 120 ° C., using an injection molding machine ("J55" manufactured by Japan Steel Works, Ltd.), cylinder temperature 260 ° C., mold temperature 80 C. to produce a molded body (absorbent resin member II) as shown in FIG.

A first member shown in Table 4 was selected, and as shown in FIG. A lid-shaped transmissive resin member I is superimposed on the resin member II, a laser light source is arranged vertically above the brim, which is the overlapped portion of the transmissive resin member I and the absorbing resin member II, and a glass plate is used to form the transmissive resin member I. and the overlapping portion of the absorbing resin member II from both sides in the thickness direction while applying a pressing force (pressing force at welding) of 4.92 N / mm in the inner direction, under the conditions shown in Table 4, laser welding by irradiating. got a body The portion indicated by symbol X in FIG. 4 is the portion irradiated with the laser.
The welding equipment is as follows.

<Galvano scanner type laser welding>
Laser device: YLR-300-AC-Y14 manufactured by IPG
Wavelength: 1070nm
Collimator: 7.5mm
Laser type: Fiber laser Intensity (output): 100W
Galvanometer scanner: Fiber Elephants 21 manufactured by ARGES
Aperture: 21mm
Laser irradiation speed: 900mm/s
Laser irradiation circumference: As shown in Table 4 or Table 5, welding part circumference: 137 mm
The position of the laser scanner was adjusted by defocusing the laser light so that the diameter of the spot irradiated onto the welding surface was 1 mm.

<Laser Welding Strength>
As shown in FIG. 5, measuring jigs 25 and 26 are inserted from the upper and lower surfaces of the box body composed of the transmissive resin member I and the absorbent resin member II produced above, respectively, and jigs 23 and 24 housed inside. and pulled up and down (pulling speed: 5 mm/min), and the strength (welding strength, unit: N) at which the transmissive resin member I and the absorbent resin member II separate was measured.
A 100 kN Tensilon universal testing machine manufactured by ORIENTEC was used as an apparatus.
The results are shown in Table 4 below.

The laser welded body obtained using the resin composition of the present invention had high laser welding strength (Example 1). On the other hand, the laser welded body obtained using the resin composition of the comparative example had low laser welding strength.

Claims (11)

Contains polyester resin and polycarbonate resin,
The mass ratio of the polyester resin and the polycarbonate resin in a total of 100 parts by mass of the polyester resin and the polycarbonate resin is 10/90 to 90/10,
The polycarbonate resin contains a recycled product,
The polycarbonate resin has a molecular weight distribution (Mw/Mn) of 2.8 or more.
Resin composition. 2. The resin composition according to claim 1, wherein the recycled product accounts for 50 parts by mass or more in 100 parts by mass of the polycarbonate resin. 3. The resin composition according to claim 1, wherein the polycarbonate resin has a viscosity-average molecular weight Mv of 20,000 or more. The resin composition according to any one of claims 1 to 3, wherein the polyester resin comprises a polybutylene terephthalate resin. The resin composition according to any one of claims 1 to 4, further comprising an inorganic filler. The resin composition according to any one of claims 1 to 5, further comprising a phosphorus stabilizer. The resin composition according to any one of claims 1 to 6, which is for laser marking. The resin composition according to any one of claims 1 to 7, which is used for a resin member that transmits laser light for laser welding. A molded article formed from the resin composition according to any one of claims 1 to 8. The molded article according to claim 9, which is for laser marking. A laser-welded article comprising the molded article according to claim 9 or 10.

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