JP2017149863A - Resin composition for laser welding and welded body thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyester resin composition for laser welding, wherein, a welded body obtained by laser welding has high tensile strength, shows black coloration with excellent coloring power, and also has excellent laser welding workability.SOLUTION: The present invention provides a resin composition for laser welding to be used in welding with a laser beam, the resin composition containing, based on (A) thermoplastic polyester resin 100 pts.mass, (B) nigrosine 0.0005-0.5 pts.mass and (C) a colorant 0.01-2 pts.mass at least comprising a specific 1: 1 azomethine nickel complex.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a laser welding resin composition and a welded body, and a welded body obtained by laser welding a molded product obtained from a laser welding resin composition has a high tensile strength, and further has a coloring power. This is a polyester resin composition for laser welding, which exhibits excellent black coloration and further has excellent laser welding processability.

Thermoplastic polyester resin has excellent mechanical strength, chemical resistance, electrical insulation, etc., and has excellent heat resistance, moldability, and recyclability, so it is widely used in various equipment parts. It has been.
In recent years, parts for automobiles have been reduced in weight in particular, and a high level of heat resistance is often demanded due to resin conversion of parts that have conventionally used metals, miniaturization of resin products, and the like. For this reason, reinforced thermoplastic resins containing fillers such as glass fibers are often used. Among them, thermoplastic polyester resins such as polybutylene terephthalate are excellent in mechanical strength and moldability, and are used in automotive electronic component cases and motor component cases. Widely used.

In recent years, an example of performing welding processing for increasing productivity has been increasing, and laser welding, which has little influence on electronic components, has been frequently used.
However, compared to polycarbonate resins, polystyrene resins, and the like, polyester resins have relatively low laser light transmittance, and warping tends to occur in molded products, so that the welding strength is often insufficient.
When warping occurs in the molded product, a method of applying a pressing force to correct the warping at the time of welding is also taken, but depending on the shape of the molded product, it is often difficult to apply the pressing force efficiently. Since residual stress remains in the welded body from which the pressing force has been removed later, there is a problem that high weld strength is difficult to obtain.

In order to improve the laser weldability of the polyester resin, a method using a copolymerized polybutylene terephthalate (Patent Document 1), a method of alloying a polybutylene terephthalate with a polycarbonate resin or a styrene resin (Patent Documents 2 and 3), Furthermore, a method of adding a specific oligomer (Patent Document 4) has been proposed.
However, in these methods, sufficient weldability may not be obtained due to a gap between welding members caused by warpage deformation of a molded product.
In addition, a method for improving weldability by adding a laser transmission absorbent such as nigrosine to a thermoplastic resin has been proposed (Patent Document 5), but a polyester resin composition suitable for laser welding has not been described. Absent.

Japanese Patent No. 3510817 Japanese Patent Laid-Open No. 2003-292752 Japanese Patent No. 4641377 JP 2004-315805 A JP 2008-1112 A

  An object of the present invention is to provide a laser-welded polyester resin composition having excellent weldability by laser, excellent black coloring power, and excellent weld strength of a welded body obtained by laser welding.

The present inventor has found that the above problems can be solved by using a combination of nigrosine and a specific colorant in the thermoplastic polyester resin, and has reached the present invention.
The present invention relates to the following laser-welded resin composition, laser-welded molded body, and laser-welded body.

[1] A resin composition used for welding by laser light, (A) 0.0005 to 0.5 parts by mass of nigrosine and (C) formula (1) with respect to 100 parts by mass of the thermoplastic polyester resin. A resin composition for laser welding, comprising 0.01 to 2 parts by mass of a colorant containing at least a 1: 1 type azomethine nickel complex shown in FIG.
In Expression ^(1), R 1 ~R ⁸ are the same or different, a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, an alkoxy group having 1 to 18 carbon atoms, a carboxy group, hydroxy group, an amino group, an alkylamino A group, a nitro group or a halogen atom. ]
[2] The resin composition for laser welding according to the above [1], wherein the colorant further contains an anthraquinone dye or a triphenylmethane dye.

[3] The laser welding resin composition according to [1] or [2], wherein the main component of (A) the thermoplastic polyester resin is a polybutylene terephthalate resin.
[4] The laser welding resin composition according to any one of the above [1] to [3], wherein an incidence rate K with respect to a 940 nm laser beam of a 1 mm thick molded plate made of the resin composition is 20 to 80%. object.
However, the incident rate K (%) = 100−transmittance−reflectance.

[5] A laser welding molded article comprising the laser welding resin composition according to any one of [1] to [4].
[6] A laser welded body of the molded product according to [5] above.
[7] The laser welded body according to the above [6], wherein the welded body has a gap of 0.1 mm or more when the welded body is welded at least at a part of the welded portion.
[8] The laser welded body according to the above [6] or [7], in which the compacts are butt-welded to each other.
[9] The laser welded body according to [6] or [7], in which the compacts are overlapped and welded.

  The resin composition for laser welding of the present invention has high heat resistance, excellent black coloring power, suitable laser welding processability, and a welded body obtained by laser welding a molded body of the resin composition has a welding strength. Excellent heat resistance.

FIG. 1 is a diagram showing an example of manufacturing a laser welded body by butting a plurality of molded bodies and performing laser welding. FIG. 2 is a diagram illustrating an example of manufacturing a laser welded body by laminating a plurality of molded bodies and performing laser welding.

  Hereinafter, although the form for implementing this invention is demonstrated in detail, the scope of the present invention is not limited to these forms. In the specification of the present application, “to” is used in the sense of including the numerical values described before and after it as the lower limit value and the upper limit value.

The resin composition for laser welding of the present invention is a resin composition used for welding by laser light, and (B) nigrosine 0.0005 to 0.5 parts by mass with respect to 100 parts by mass of (A) thermoplastic polyester resin. And (C) 0.01 to 2 parts by mass of a colorant containing at least a 1: 1 type azomethine nickel complex represented by formula (1).
In Expression ^(1), R 1 ~R ⁸ are the same or different, a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, an alkoxy group having 1 to 18 carbon atoms, a carboxy group, hydroxy group, an amino group, an alkylamino A group, a nitro group or a halogen atom. ]

[(B) Nigrosine]
The resin composition for laser welding of the present invention contains (B) nigrosine in an amount of 0.0005 to 0.5 parts by weight, preferably 0.001 to 0.005 parts per 100 parts by weight of (A) the thermoplastic polyester resin. 1 mass part, More preferably, 0.003-0.05 mass part is contained.
Nigrosine works as a dye having laser light absorption and has gentle absorption in the range of laser light in the range of 800 nm to 1200 nm.
Nigrosine is C.I. I. Solvent Black 5 and C.I. I. It is a black azine-based condensation mixture as described in Color Index as Solvent Black 7. This can be synthesized, for example, by oxidizing and dehydrating condensation of aniline, aniline hydrochloride and nitrobenzene at a reaction temperature of 160 to 190 ° C. in the presence of iron chloride. Examples of commercially available nigrosine include “NUBIAN (registered trademark) BLACK series” (both trade names, manufactured by Orient Chemical Industry Co., Ltd.).

The content of (B) nigrosine is 0.0005 to 0.5 parts by mass with respect to 100 parts by mass of (A) the thermoplastic polyester resin. 0.1 parts by mass, more preferably 0.003 to 0.05 parts by mass, and still more preferably 0.005 to 0.03 parts by mass. By adjusting the content of nigrosine in such a range, the incidence rate K of the resin composition for laser welding can be 20 to 80%, preferably 40 to 70%.
In addition, the said content is the quantity with respect to a total of 100 mass parts of these resin, when (A) thermoplastic polyester resin which is mentioned later contains polycarbonate resin and / or aromatic vinyl resin together.

Moreover, the resin composition for laser welding may contain the other absorptive dye with respect to a laser beam, or a laser beam absorber in the effective range which can implement this invention.
The incidence rate K (unit:%) is defined by the following equation.
Incident rate K (%) = 100−transmittance−reflectance

[(C) Colorant]
The colorant (C) used in the resin composition of the present invention is a colorant containing at least a 1: 1 type azomethine nickel complex represented by the following formula (1).
In Expression ^(1), R 1 ~R ⁸ are the same or different, a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, an alkoxy group having 1 to 18 carbon atoms, a carboxy group, hydroxy group, an amino group, an alkylamino A group, a nitro group or a halogen atom. ]

Examples of the alkyl group having 1 to 18 carbon atoms in R ^{1 to} R ⁸ in the formula (1) include a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, and an i-butyl group. , Sec-butyl group, t-butyl group, n-pentyl group, neo-pentyl group, i-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, 2-ethylhexyl group, n-decyl group Preferred examples of the alkoxy group having 1 to 18 carbon atoms include methoxy group, ethoxy group, n-propoxy group, i-propoxy group, n-butoxy group, i-butoxy group, sec-butoxy group, A t-butoxy group, an n-pentyloxy group, a neo-pentyloxy group, an n-hexyloxy group, an n-heptyloxy group, an n-octyloxy group, and the like are preferable. , For example, methylamino group, dimethylamino group, ethylamino, diethylamino, and the like preferably, a halogen atom, for example, F, Cl, Br or the like.

  The azomethine dye used for the 1: 1 type azomethine nickel complex can be produced by a known method. For example, it can be obtained by reacting diaminomaleonitrile as shown in the following reaction formula with salicylaldehyde which may have a substituent.

In formula (2), R ^{1 to} R ⁸ have the same meaning as in formula (1).

  By metallizing this azomethine dye with a nickelating agent such as nickel acetate, a 1: 1 type azomethine nickel complex is obtained as shown below.

In formula (3), R ^{1 to} R ⁸ have the same meaning as in formula (1).
In the obtained nickel complex, the azomethine dye functions as a chelating four ligand and constitutes a stable complex.

  Since 1: 1 type azomethine nickel complex has good fastness such as heat resistance and light resistance, it is useful for resin compositions for outdoor parts and parts exposed to heat, and heat changes upon melting during laser welding. Is less likely to occur and is suitable as a colorant for laser welding members.

Specific examples of the 1: 1 type azomethine nickel complex represented by the formula (1) preferably include compound examples 1 to 7 in Table 1 below in which R ^{1 to} R ⁸ are as follows.
The azomethine nickel complex used in the present invention is not limited to these.

  The (C) colorant used in the present invention is a colorant containing at least a 1: 1 type azomethine nickel complex. The azomethine nickel complex may be prepared by using another colorant, for example, in order that the above compound example 1 is brown, compound example 2 is brown, compound example 3 is reddish brown, compound example 6 is purple, and black. Need to be mixed.

Examples of the colorant include mixed dye pigments containing at least the azomethine nickel complex. For example, a method of blending a blue dye, a violet dye, and a green dye and blending a red dye or a yellow dye as necessary to adjust the color tone is exemplified.
Examples of dyes and pigments that can be blended in this way are acid dyes, basic dyes, mordants / acid mordant dyes, alcohol-soluble dyes, azoic dyes, sulfurized / sulfurized vat dyes, vat dyes, disperse dyes, oil-soluble dyes, food dyes And dyes such as metal complex dyes and organic pigments.

Specific examples of the dye include azo dyes, quinacridone dyes, dioxazine dyes, quinophthalone dyes, perinone dyes, perylene dyes, isoindolinone dyes, azomethine dyes, triphenylmethane dyes, anthraquinone dyes, and the like. Of the above colorants, anthraquinone dyes or triphenylmethane dyes are preferred. The anthraquinone dye preferably has a maximum absorption wavelength in the range of 590 to 635 nm, and more preferably has a maximum absorption wavelength in the range of 577 to 628 nm. The triphenylmethane dye is preferably blue, and the anthraquinone dye is preferably blue.
As the colorant, in order to obtain a polyester resin with high blackness, the content ratio of the anthraquinone dye or triphenylmethane dye is preferably 15 to 45% by mass in 100% by mass of the colorant, Furthermore, 20-40 mass% is preferable.

  Specific examples of the pigment include organic pigments such as azo pigments, condensed azo pigments, phthalocyanine pigments, anthraquinone pigments, quinacdolin pigments, isoindolinone pigments, diketopyrrolopyrrole pigments, and various lake pigments.

(C) Content of a coloring agent is 0.01-2 mass parts with respect to 100 mass parts of (A) thermoplastic polyester resin, Preferably it is 0.05-0.8 mass part, More preferably, it is 0.00. 1 to 0.5 parts by mass. By adjusting the content of the colorant to such a range, a laser welding resin composition having a high black coloring power can be obtained.
In addition, the said content is the quantity with respect to a total of 100 mass parts of these resin, when (A) thermoplastic polyester resin which is mentioned later contains polycarbonate resin and / or aromatic vinyl resin together.

[(A) Thermoplastic polyester resin]
The thermoplastic polyester resin (A) contained in the laser welding resin composition of the present invention 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. It may be either a homopolyester or a copolyester.

(A) As a dicarboxylic acid compound which comprises a thermoplastic polyester resin, aromatic dicarboxylic acid or its ester-forming derivative is used preferably.
As aromatic dicarboxylic acids, 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, diphenyl ether-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 -Terphenylene-4,4'-dicarboxylic acid, pyridine-2,5-dicarboxylic acid, etc. Refutaru acid can be preferably used.

These aromatic dicarboxylic acids may be used as a mixture of two or more. As is well known, these compounds can be used in polycondensation reactions with dimethyl esters or the like as ester-forming derivatives in addition to free acids.
If the amount is small, together with these aromatic dicarboxylic acids, aliphatic dicarboxylic acids such as adipic acid, azelaic acid, dodecanedioic acid, sebacic acid, 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid and 1 One or more alicyclic dicarboxylic acids such as 1,4-cyclohexanedicarboxylic acid can be mixed and used.

(A) Examples of the dihydroxy compound constituting the thermoplastic polyester resin include ethylene glycol, propylene glycol, butanediol, hexylene glycol, neopentyl glycol, 2-methylpropane-1,3-diol, diethylene glycol, and triethylene glycol. Aliphatic diols, alicyclic diols such as cyclohexane-1,4-dimethanol, etc., and mixtures thereof. If the amount is small, one or more long-chain diols having a molecular weight of 400 to 6000, that is, polyethylene glycol, poly-1,3-propylene glycol, polytetramethylene glycol, and the like may be copolymerized.
In addition, aromatic diols such as hydroquinone, resorcin, naphthalenediol, dihydroxydiphenyl ether, and 2,2-bis (4-hydroxyphenyl) propane can also be used.

  In addition to the above bifunctional monomers, trifunctional monomers such as trimellitic acid, trimesic acid, pyromellitic acid, pentaerythritol, and trimethylolpropane are introduced to introduce a branched structure, and fatty acids are used for molecular weight control. A small amount of the monofunctional compound can be used in combination.

  As the (A) thermoplastic polyester resin, usually, a resin mainly composed of polycondensation of a dicarboxylic acid and a diol, that is, a resin comprising 50% by mass, preferably 70% by mass or more of the entire resin, is composed of this polycondensate. The dicarboxylic acid is preferably an aromatic carboxylic acid, and the diol is preferably an aliphatic diol.

  Preferred is polyalkylene terephthalate 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. Typical examples are polybutylene terephthalate and polyethylene terephthalate. These are preferably close to homopolyester, that is, 95% by mass or more of the entire resin is composed of a terephthalic acid component and a 1,4-butanediol or ethylene glycol component.

In the resin composition of the present invention, the main component is preferably polybutylene terephthalate. From the viewpoint of laser weldability, polybutylene terephthalate in which polyalkylene glycol such as isophthalic acid, dimer acid, polytetramethylene glycol (PTMG) or the like is copolymerized is also preferable.
In addition, in this invention, a main component means that it is 50 mass% or more in 100 mass% of resin components in a resin composition.

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

  When dimer acid copolymerized polybutylene terephthalate is used as the polybutylene terephthalate, the proportion of the dimer acid component in the total carboxylic acid component is preferably 0.5 to 30 mol% as the carboxylic acid group, and 1 to 20 More preferably, mol% is more preferable, and 3-15 mol% is still more preferable. By setting it as such a copolymerization ratio, it exists in the tendency which is excellent in the balance of laser weldability, long-term heat resistance, and toughness, and is preferable.

  When isophthalic acid copolymerized polybutylene terephthalate is used as the polybutylene terephthalate, the proportion of the isophthalic acid component in the total carboxylic acid component is preferably 1 to 30 mol% as the carboxylic acid group, and 1 to 20 mol%. Is more preferable, and 3-15 mol% is still more preferable. By setting it as such a copolymerization ratio, it exists in the tendency which is excellent in the balance of laser weldability, heat resistance, injection moldability, and toughness, and is preferable.

  Among these copolymers, copolymerized polybutylene terephthalate copolymerized with polytetramethylene glycol or isophthalic acid copolymerized polybutylene terephthalate is preferable.

(A) The intrinsic viscosity of the thermoplastic polyester resin is preferably 0.5 to 2 dl / g. In view of moldability and mechanical properties, those having an intrinsic viscosity in the range of 0.6 to 1.5 dl / g are preferred. If the intrinsic viscosity is lower than 0.5 dl / g, the resulting resin composition tends to have a low mechanical strength. Moreover, if it is higher than 2 dl / g, the fluidity of the resin composition may be deteriorated and the moldability may be deteriorated or the laser weldability may be deteriorated.
The intrinsic viscosity of the thermoplastic polyester resin is measured at 30 ° C. in a 1: 1 (mass ratio) mixed solvent of tetrachloroethane and phenol.

  (A) The terminal carboxyl group amount of the thermoplastic polyester resin may be appropriately selected and determined, but is usually 60 eq / ton or less, preferably 50 eq / ton or less, and 30 eq / ton or less. Is more preferable. If it exceeds 50 eq / ton, gas tends to be generated during melt molding of the resin composition. Although the lower limit of the amount of terminal carboxyl groups is not particularly defined, it is usually 10 eq / ton in consideration of the productivity in the production of (A) thermoplastic polyester resin.

  The amount of terminal carboxyl groups of (A) thermoplastic polyester resin is such that 0.5 g of (A) thermoplastic polyester resin is dissolved in 25 mL of benzyl alcohol, and 0.01 mol / l benzyl alcohol solution of sodium hydroxide is used. It is a value measured by titration. As a method for adjusting the amount of terminal carboxyl groups, a conventionally known arbitrary method such as a method for adjusting polymerization conditions such as a raw material charge ratio during polymerization, a polymerization temperature, a pressure reduction method, a method for reacting a terminal blocking agent, etc. Just do it.

  In the present invention, it is also preferred that (A) the thermoplastic polyester resin contains a polybutylene terephthalate homopolymer and a polybutylene terephthalate copolymer. At this time, the content of the polybutylene terephthalate copolymer is preferably 5 to 70% by mass, more preferably 100% by mass of the polybutylene terephthalate homopolymer and 100% by mass of the polybutylene terephthalate copolymer. It is 10-65 mass%, More preferably, it is 20-60 mass%, Most preferably, it is 30-55 mass%. When the content of the polybutylene terephthalate copolymer is less than 5% by mass, the laser transmittance and the laser welding strength are liable to be lowered, and when it exceeds 70% by mass, the moldability is liable to be lowered.

  Moreover, in this invention, it is also preferable that (A) thermoplastic polyester resin contains polybutylene terephthalate resin and polyethylene terephthalate resin. At this time, the content of the polyethylene terephthalate resin is preferably 5 to 50% by mass, more preferably 10 to 45% by mass, with respect to 100% by mass in total of the polybutylene terephthalate resin and the polyethylene terephthalate resin. More preferably, it is 15-40 mass%. When the content of the polyethylene terephthalate resin is less than 5% by mass, the laser light transmittance and the laser welding strength tend to be lowered, and when it exceeds 50% by mass, the moldability tends to be lowered.

  The intrinsic viscosity of the polyethylene terephthalate resin is preferably 0.5 to 2 dl / g, and more preferably has an intrinsic viscosity in the range of 0.6 to 1.5 dl / g in terms of moldability and mechanical properties. preferable. When a material having an intrinsic viscosity lower than 0.5 dl / g is used, the resulting molded product of the resin composition tends to have a low mechanical strength. On the other hand, if it is higher than 2 dl / g, the fluidity of the resin composition may deteriorate and the moldability may deteriorate.

  In the present invention, it is also preferred that (A) the thermoplastic polyester resin is a polybutylene terephthalate resin and further contains a polycarbonate resin. In that case, the content of the polycarbonate resin is preferably 10 to 50% by mass, more preferably 15 to 45% by mass, and still more preferably 20 to 100% by mass of the total of the polybutylene terephthalate resin and the polycarbonate resin. -40 mass%. When the content of the polycarbonate resin is less than 10% by mass, the laser light transmittance and the laser welding strength are liable to decrease, and when it exceeds 50% by mass, the moldability may be decreased.

The viscosity average molecular weight of the polycarbonate resin is preferably 5,000 to 30,000, more preferably 10,000 to 28,000, and still more preferably 14,000 to 24,000. If a material having a viscosity average molecular weight lower than 5000 is used, the obtained welding member tends to have a low mechanical strength. On the other hand, if it is higher than 30000, the fluidity of the resin composition may be deteriorated and the moldability may be deteriorated or the laser weldability may be deteriorated.
The viscosity average molecular weight of the polycarbonate resin is a viscosity average molecular weight [Mv] converted from a solution viscosity measured at a temperature of 25 ° C. using methylene chloride as a solvent.

  Further, the ratio (Mw / Mn) of polystyrene-equivalent weight average molecular weight Mw and number average molecular weight Mn measured by gel permeation chromatography (GPC) of the polycarbonate resin is preferably 2 to 5, 2.5-4 are more preferable. When Mw / Mn is too small, the fluidity in the molten state increases and the moldability tends to decrease. On the other hand, if Mw / Mn is excessively large, the melt viscosity tends to increase and molding becomes difficult.

  The amount of terminal hydroxy groups of the polycarbonate resin is preferably 100 ppm by mass or more, more preferably 200 ppm by mass or more, and still more preferably 400 ppm by mass, from the viewpoints of thermal stability, hydrolysis stability, color tone, and the like. As mentioned above, Most preferably, it is 500 mass ppm or more. However, it is usually 1500 mass ppm or less, preferably 1300 mass ppm or less, more preferably 1200 mass ppm or less, and most preferably 1000 mass ppm or less. When the amount of terminal hydroxy groups of the polycarbonate resin is too small, the laser transmittance tends to be lowered, and the initial hue at the time of molding may be deteriorated. When the amount of terminal hydroxy groups is excessively large, the residence heat stability and the moist heat resistance tend to decrease.

  The production method of the polycarbonate resin is not particularly limited, and a polycarbonate resin produced by any of the phosgene method (interfacial polymerization method) and the melt polymerization method (transesterification method) can be used. Among these, as the polycarbonate resin, a polycarbonate resin produced by a melt polymerization method is preferable from the viewpoints of laser light transmittance and laser weldability.

  In the present invention, it is also preferred that (A) the thermoplastic polyester resin is a polybutylene terephthalate resin and further contains an aromatic vinyl resin. In this case, the content of the aromatic vinyl resin is preferably 10 to 50% by mass, more preferably 15 to 45% by mass with respect to 100% by mass of the total of the polybutylene terephthalate resin and the aromatic vinyl resin. Yes, more preferably 20 to 40% by mass. When the content of the aromatic vinyl resin is less than 10% by mass, the laser light transmittance and the laser welding strength are likely to be lowered, and when it exceeds 50% by mass, the heat resistance and the heat discoloration are easily lowered.

The aromatic vinyl resin is a polymer mainly composed of an aromatic vinyl compound. Examples of the aromatic vinyl compound include styrene, α-methylstyrene, paramethylstyrene, vinyltoluene, and vinylxylene. Styrene is preferred. A typical example of the aromatic vinyl resin is polystyrene (PS).
As the aromatic vinyl resin, a copolymer obtained by copolymerizing an aromatic vinyl compound with another monomer can also be used. A typical example is an acrylonitrile-styrene copolymer (AS resin) in which styrene and acrylonitrile are copolymerized.

As the aromatic vinyl resin, a rubber-containing aromatic vinyl resin obtained by copolymerizing or blending rubber components can also be preferably used. Examples of the rubber component include conjugated diene hydrocarbons such as butadiene, isoprene and 1,3-pentadiene. In the present invention, butadiene rubber is preferably used. An acrylic rubber component can be used as the rubber component, but it is not preferable because it is poor in terms of toughness.
When the rubber component is copolymerized or blended, the amount of the rubber component is usually 1% by mass or more and less than 50% by mass, preferably 3 to 40% by mass, more preferably 5 to 5% in all segments of the aromatic vinyl resin. 30 mass%, More preferably, it is 5-20 mass%.
As the rubber component-containing aromatic vinyl resin, rubber-containing polystyrene is preferable, butadiene rubber-containing polystyrene is more preferable, and high impact polystyrene (HIPS) is particularly preferable from the viewpoint of toughness.
As the aromatic vinyl resin, polystyrene, acrylonitrile-styrene copolymer (AS resin) and butadiene rubber-containing polystyrene are preferable, and polystyrene and high impact polystyrene (HIPS) are particularly preferable.

  As an aromatic vinyl-type resin, it is preferable that the mass mean molecular weights measured by GPC are 50,000 to 500,000, and especially 100,000 to 400,000, and especially 150,000 to 300,000 are preferable. If the molecular weight is less than 50,000, bleeding out is observed in the molded product, or decomposition gas is generated during molding, and it is difficult to obtain sufficient weld strength. If the molecular weight is greater than 500,000, sufficient fluidity and laser welding strength are obtained. It is difficult to improve.

The aromatic vinyl resin preferably has a melt flow rate (MFR) measured at 200 ° C. and 98 N of 0.1 to 50 g / 10 minutes, more preferably 0.5 to 30 g / 10 minutes. Preferably, it is 1-20 g / 10min. If the MFR is smaller than 0.1 g / 10 min, the compatibility with the (A1) polybutylene terephthalate resin tends to be insufficient, and the appearance of delamination may occur during injection molding. On the other hand, if the MFR is larger than 50 g / 10 minutes, the impact resistance may be greatly reduced, which is not preferable.
In particular, when the aromatic vinyl resin is polystyrene, the MFR is preferably 1 to 50 g / 10 min, more preferably 3 to 35 g / 10 min, and 5 to 20 g / 10 min. Is more preferable. When the aromatic vinyl resin is a butadiene rubber-containing polystyrene, the MFR is preferably 0.1 to 40 g / 10 min, more preferably 0.5 to 30 g / 10 min, and 1 to 20 g / More preferably, it is 10 minutes.

  Further, in the present invention, it is preferable that (A) the thermoplastic polyester resin is a polybutylene terephthalate resin, and further contains an aromatic vinyl resin and a polycarbonate resin. The content ratio in that case is based on a total of 100 mass% of these resins, the polybutylene terephthalate resin is 30 to 90 mass%, and the aromatic vinyl resin and the polycarbonate resin are each 50 mass% at most. preferable.

  Further, when polybutylene terephthalate resin, aromatic vinyl resin and polycarbonate resin are included, the more preferable content of polybutylene terephthalate resin is based on a total of 100% by mass of polybutylene terephthalate resin, aromatic vinyl resin and polycarbonate resin. 40 to 80% by mass, and more preferably 50 to 70% by mass. When the content is less than 30% by mass, the heat resistance tends to be lowered, and when it exceeds 90% by mass, the laser transmittance tends to be lowered.

  Further, the content of the aromatic vinyl resin is more preferably 1 to 50% by mass, and further preferably 3 to 45% by mass with respect to 100% by mass in total of the polybutylene terephthalate resin, the aromatic vinyl resin and the polycarbonate resin. Especially preferably, it is 5-40 mass%. If the content is less than 1% by mass, the laser weldability and toughness become poor, and if it exceeds 50% by mass, the heat resistance tends to decrease.

  Further, the content of the polycarbonate resin is more preferably 1 to 50% by mass, still more preferably 3 to 45% by mass, particularly preferably 100% by mass with respect to the total of 100% by mass of the polybutylene terephthalate resin, the aromatic vinyl resin and the polycarbonate resin. Is 5-40 mass%. When the content is less than 1% by mass, the laser light transmittance and the laser weldability are liable to be lowered, and the dispersion of the aromatic vinyl resin is poor, and the surface appearance of the molded product is liable to be lowered. If it exceeds 50% by mass, transesterification with the polybutylene terephthalate resin proceeds, and the residence heat stability tends to decrease.

  The total content of the aromatic vinyl resin and the polycarbonate resin is preferably 10 to 55% by mass with respect to 100% by mass of the total of the polybutylene terephthalate resin, the aromatic vinyl resin and the polycarbonate resin, and 20 to 20%. 50 mass% is more preferable, and 25-45 mass% is still more preferable. By setting it as such content, it exists in the tendency which is excellent in the balance of heat resistance and laser beam transmittance, and is preferable.

  In addition, the content ratio of the aromatic vinyl resin and the polycarbonate resin component is preferably 5: 1 to 1: 5, more preferably 4: 1 to 1: 4, in terms of mass ratio. By setting it as such a content ratio, it exists in the tendency which is excellent in the balance of heat resistance and laser beam transmittance, and is preferable.

When polybutylene terephthalate resin, aromatic vinyl resin, and polycarbonate resin are included, the crystallization temperature (Tc) of the obtained resin composition is preferably 190 ° C. or lower. That is, laser transmissivity can be further improved by appropriately suppressing the transesterification reaction between the polybutylene terephthalate resin and the polycarbonate resin and appropriately reducing the crystallization temperature. The crystallization temperature (Tc) is more preferably 188 ° C. or lower, further preferably 185 ° C. or lower, particularly preferably 182 ° C. or lower, and most preferably 180 ° C. or lower. Moreover, the minimum is 160 degreeC normally, Preferably it is 165 degreeC or more.
The crystallization temperature (Tc) was raised at a heating rate of 20 ° C./min from 30 to 300 ° C. under a nitrogen atmosphere using a differential scanning calorimetry (DSC) machine and held at 300 ° C. for 3 minutes. Thereafter, it is measured as a peak top temperature of an exothermic peak observed when the temperature is lowered at a temperature lowering rate of 20 ° C./min.

  The laser welding resin composition of the present invention can be blended with various additives as desired. Such additives include, for example, reinforcing fillers, impact modifiers, flow modifiers, auxiliary colorants, dispersants, stabilizers, plasticizers, UV absorbers, light stabilizers, antioxidants, charging Examples include inhibitors, lubricants, mold release agents, crystal accelerators, crystal nucleating agents, flame retardants, and epoxy compounds.

The reinforcing filler contained in the resin composition of the present invention has the effect of improving the mechanical properties of the resin composition obtained by blending with the resin, and a conventional inorganic filler for plastics should be used. Can do. Preferably, fibrous fillers such as glass fiber, carbon fiber, basalt fiber, wollastonite and potassium titanate fiber can be used. In addition, granular or amorphous fillers such as calcium carbonate, titanium oxide, feldspar minerals, clay, organic clay, glass beads, etc .; plate-like fillers such as talc; scaly forms such as glass flakes, mica and graphite A filler can also be used. Among these, it is preferable to use glass fiber from the viewpoints of laser light transmittance, mechanical strength, rigidity, and heat resistance.
More preferably, the reinforcing filler is surface-treated with a surface treatment agent such as a coupling agent. The glass fiber to which the surface treatment agent is attached is preferable because it is excellent in durability, heat and humidity resistance, hydrolysis resistance, and heat shock resistance.

  As the surface treatment agent, any conventionally known one can be used. Specifically, for example, silane coupling agents such as amino silane, epoxy silane, allyl silane, and vinyl silane are preferable. Among these, aminosilane-based surface treatment agents are preferable, and specifically, for example, γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, and γ- (2-aminoethyl) aminopropyltrimethoxysilane are preferable. Take as an example.

Other examples of the surface treatment agent include a novolac type epoxy resin surface treatment agent, a bisphenol A type epoxy resin surface treatment agent, and the like, and a treatment with a novolac type epoxy resin surface treatment agent is particularly preferable.
The silane-based surface treatment agent and the epoxy resin-based surface treatment agent may be used singly or in combination, and it is also preferable to use both in combination.

The glass fiber is preferably a glass fiber having an anisotropic cross-sectional shape in which the ratio of the major axis to the minor axis in the cross section is 1.5 to 10 from the viewpoints of laser weldability and heat shock resistance. The cross-sectional shape is preferably one having a rectangular or oval cross section, and a major axis / minor axis ratio of 2.5 to 8, more preferably 3 to 6. When the major axis is D ₂ , the minor axis is D ₁ , and the average fiber length is L, the aspect ratio ((L × 2) / (D ₂ + D ₁ )) is preferably 10 or more. When such flat glass fibers are used in this way, the warpage of the molded product is suppressed, which is particularly effective when manufacturing a box-shaped welded body.

The content of the reinforcing filler is preferably 5 to 150 parts by mass with respect to 100 parts by mass of the (A) thermoplastic polyester resin. When the content of the reinforcing filler is less than 5 parts by mass, sufficient strength and heat resistance are difficult to obtain, and when it exceeds 150 parts by mass, fluidity and laser weldability tend to be lowered. A more preferable content of the reinforcing filler is 15 to 130 parts by mass, more preferably 30 to 120 parts by mass, and particularly 40 to 100 parts by mass.
In addition, said content is an quantity with respect to a total of 100 mass parts of these resin, when the above-mentioned (A) thermoplastic polyester resin contains polycarbonate resin and / or aromatic vinyl resin together. The same applies to the case where the content of other additives is described below.

  The impact resistance improver contained in the resin composition of the present invention functions to improve the heat shock resistance of the resin composition. The impact resistance improver is not particularly limited as long as it has the effect of improving the impact resistance of the resin, but is not limited to polyester elastomer, polyolefin elastomer, acrylic elastomer, polyamide elastomer, polyurethane elastomer, fluorine elastomer. , Silicone-based elastomers, acrylic core / shell type elastomers, and the like, and polyester-based elastomers and styrene-based elastomers are preferable.

  The polyester elastomer is a thermoplastic polyester having rubber properties at room temperature, preferably a thermoplastic elastomer mainly composed of a polyester block copolymer, and has a high melting point and high crystallinity as a hard segment. A block copolymer having an amorphous polyester or an amorphous polyether as a soft segment is preferable. The content of the soft segment of the polyester-based elastomer is at least 20 to 95 mol% in all segments, and in the case of a block copolymer of polybutylene terephthalate and polytetramethylene glycol (PBT-PTMG copolymer), 50 to 95 mol%. The content of the preferred soft segment is 50 to 90 mol%, particularly 60 to 85 mol%. Among these, a polyester ether block copolymer, particularly a PTMG-PBT copolymer, is preferable because a decrease in transmittance is reduced.

  Specific examples of polyester elastomers include “Primalloy” (trade name, registered trademark (hereinafter the same)) manufactured by Mitsubishi Chemical Corporation, “Perprene” (manufactured by Toyobo), “Hytrel” (manufactured by Toray DuPont), “ “Byron” (manufactured by Toyobo Co., Ltd.), “Polyester” (manufactured by Nippon Synthetic Chemical Industry Co., Ltd.) and the like are preferred.

Moreover, as a styrene-type elastomer, it consists of a styrene component and an elastomer component, and what contains a styrene component normally in the ratio of 5-80 mass%, Preferably it is 10-50 mass%, Especially 15-30 mass% is preferable. Examples of the elastomer component at this time include conjugated diene hydrocarbons such as butadiene, isoprene and 1,3-pentadiene. More specifically, a copolymer of styrene and butadiene (SBS) elastomer, styrene and Examples thereof include a copolymer (SIS) elastomer with isoprene.
It is also preferable to use a resin (SEBS, SEPS) obtained by hydrogenating the above SBS elastomer or SIS elastomer.

  Specific examples of styrene elastomers include “Dynalon” (manufactured by JSR, trade name and registered trademark (hereinafter the same)), “Tuftec” (manufactured by Asahi Kasei Chemicals), “Hibler”, “Septon” (manufactured by Kuraray) Etc.

As the impact modifier, a copolymer-type elastomer containing an epoxy group is also preferable because it has good reactivity with the (A) thermoplastic polyester resin and there is little decrease in laser transmittance.
The type of copolymer elastomer containing an epoxy group is not limited. For example, those obtained by introducing an epoxy group into the above-described styrene elastomer, polyolefin elastomer, acrylic elastomer and the like are preferable. For example, in the case of a styrene-butadiene copolymer obtained by copolymerizing polystyrene as a hard segment and butadiene as a soft segment, an epoxy group-containing elastomer can be obtained by epoxidizing an unsaturated double bond portion of a diene component.
In addition, the olefin elastomer may have a polyolefin part in the soft phase, and EPR, EPDM, etc. can be preferably used.
The method for introducing an epoxy group is not particularly limited, and it may be incorporated into the main chain, or a polymer containing an epoxy group may be introduced into the olefin elastomer in a block or graft form. Preferably, a (co) polymer having an epoxy group is introduced in a graft form.

  Specific examples of copolymer-type elastomers containing epoxy groups include “Bond First” (trade name, registered trademark (hereinafter the same)) manufactured by Sumitomo Chemical Co., Ltd., “Rotada” (manufactured by Arkema), “Elvalloy” (Mitsui DuPont Polychemical Co., Ltd., “Paraloid” (Rohm and Haas Co., Ltd.), “Metabrene” (Mitsubishi Rayon Co., Ltd.), “Epofriend” (Daicel Chemical Industries Co., Ltd.) and the like.

  The impact resistance improver may be used alone or in combination of two or more. The content of the impact resistance improver is 0 to 20 parts by mass, preferably 1 to 18 parts by mass, more preferably 2 to 15 parts by mass, and still more preferably 3 to 100 parts by mass of the (A) thermoplastic polyester resin. 12 parts by mass, particularly preferably 3 to 7 parts by mass. If the content of the impact resistance improver exceeds 20 parts by mass, the heat resistance rigidity tends to decrease.

The epoxy compound functions to improve the laser weldability and heat-and-moisture resistance of the resin composition, and to further improve the strength and durability of the weld part of the molded product.
The epoxy compound is not particularly limited as long as it has one or more epoxy groups in one molecule, and is usually a glycidyl compound which is a reaction product of alcohol, phenol or carboxylic acid and epichlorohydrin, or an olefinic compound. A compound obtained by epoxidizing a heavy bond may be used.
Preferable specific examples of the epoxy compound include, for example, bisphenol type epoxy compounds such as bisphenol A type epoxy compounds and bisphenol F type epoxy compounds, resorcin type epoxy compounds, novolac type epoxy compounds, alicyclic compound type diepoxy compounds, glycidyl ethers, Examples thereof include glycidyl esters and epoxidized polybutadiene.
Examples of the alicyclic compound type epoxy compound include vinylcyclohexene dioxide and dicyclopentadiene oxide.

Specific examples of glycidyl ethers include monoglycidyl ethers such as methyl glycidyl ether, butyl glycidyl ether, 2-ethylhexyl glycidyl ether, decyl glycidyl ether, stearyl glycidyl ether, phenyl glycidyl ether, butylphenyl glycidyl ether, and allyl glycidyl ether; Examples include pentyl glycol diglycidyl ether, ethylene glycol diglycidyl ether, glycerin diglycidyl ether, propylene glycol diglycidyl ether, and bisphenol A diglycidyl ether.
Examples of glycidyl esters include monoglycidyl esters such as benzoic acid glycidyl ester and sorbic acid glycidyl ester; adipic acid diglycidyl ester, terephthalic acid diglycidyl ester, orthophthalic acid diglycidyl ester, and the like.

  The epoxy compound may be a copolymer having a glycidyl group-containing compound as one component. For example, a copolymer of a glycidyl ester of α, β-unsaturated acid and one or more monomers selected from the group consisting of α-olefin, acrylic acid, acrylic ester, methacrylic acid, and methacrylic ester Can be mentioned.

The epoxy compound is preferably an epoxy compound having an epoxy equivalent of 100 to 500 g / eq and a number average molecular weight of 2000 or less. When the epoxy equivalent is less than 100 g / eq, since the amount of the epoxy group is too large, the viscosity of the resin composition is increased, and the adhesiveness of the weld portion is likely to be reduced. On the contrary, when the epoxy equivalent exceeds 500 g / eq, the amount of the epoxy group decreases, and thus the effect of improving the heat and moisture resistance of the resin composition tends not to be sufficiently exhibited. Moreover, the thing whose number average molecular weight exceeds 2000 has a tendency for compatibility with (A) thermoplastic polyester resin to fall, and for the mechanical strength of a molded article to fall.
As the epoxy compound, a bisphenol A type epoxy compound or a novolac type epoxy compound obtained from a reaction of bisphenol A or novolak with epichlorohydrin is particularly preferable.

  Although content of an epoxy compound is 0-5 mass parts with respect to 100 mass parts of (A) thermoplastic polyester resins, it is preferable to contain 0.1 mass part or more in order to express an effect. If the content is more than 3 parts by mass, crosslinking may proceed and the fluidity at the time of molding may be deteriorated, so 0.2 to 3 parts by mass, particularly 0.2 to 2 parts by mass is preferable.

  Examples of the flow modifier include styrene oligomers, olefin oligomers, acrylic oligomers, polyfunctional compounds, branched polymers (including dendrimers (dendritic polymers), highly branched, hyperbranched, and cyclic oligomers). Is preferably exemplified and plays a role of imparting fluidity and maintaining mechanical strength. In particular, when a box-shaped welded body or a welded body having a flow length of 70 mm or more is produced, the addition of a flow modifier is effective.

The styrene oligomer is a polymer having a vinyl aromatic compound as a main component, and examples of the vinyl aromatic compound include styrene, α-methylstyrene, paramethylstyrene, vinyltoluene, and vinylxylene. Is styrene. Styrene oligomers include polystyrene, rubber-modified polystyrene, acrylonitrile-styrene, acrylonitrile-butadiene-styrene, methyl methacrylate-butadiene-styrene, acrylonitrile-acrylic acid-styrene, styrene-maleic acid copolymer, styrene-butadiene-styrene copolymer. Typical examples include polymer oligomers and hydrides thereof. Of these, styrene oligomers and acrylonitrile-styrene oligomers are particularly preferred from the viewpoint of physical properties and cost.
Styrene-based oligomers can also be obtained as commercial products. Examples of commercially available products include the product name “Alfon (registered trademark) UP-1150” manufactured by Toa Gosei Co., Ltd., the product name “YS Resin” SX-100 "and the like are preferable.

  The styrene-based oligomer preferably has a relatively small mass average molecular weight. Specifically, the mass average molecular weight is 1000 to 10,000, and among these, 1500 to 7500, particularly 2000 to 6000 is preferable. If the mass average molecular weight is less than 1000, bleed out occurs in the molded product, or decomposition gas is generated during molding, making it difficult to obtain sufficient weld strength. On the other hand, if the mass average molecular weight is greater than 10,000, it is difficult to improve sufficient fluidity and weld strength. In addition, a mass average molecular weight says the value of polystyrene conversion by a gel permeation chromatography (GPC) method.

  The content of the styrene-based oligomer is preferably 0.5 to 10 parts by mass, more preferably 2 to 10 parts by mass, and further preferably 3 to 7 parts by mass with respect to 100 parts by mass of the (A) thermoplastic polyester resin. .

The olefin oligomer is preferably one having an α-olefin having 2 to 5 carbon atoms as the monomer unit. Among them, ethylene and propylene are preferable, and an oligomer obtained by copolymerizing this with another copolymerizable monomer is particularly preferable.
As the copolymerization monomer, an acrylic monomer, particularly an alkyl acrylate or an alkyl methacrylate, is preferable. Examples thereof include methyl methacrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, and 2-ethylhexyl acrylate. Further, it may be end-modified with (anhydrous) maleic acid or the like.
Olefin-based oligomers can also be obtained as commercial products. Examples of commercially available products include those manufactured by Arkema Co., Ltd., trade names “Rotril (registered trademark) 37EH550”, “35BA320”, Nippon Unicar Company Limited, trade names “ NUC-6070 "etc. are mentioned preferably.

The olefin oligomer preferably has a mass average molecular weight of about 2000 to 20000, more preferably 3000 to 15000, and particularly preferably 5000 to 15000. If the molecular weight is less than 2000, bleeding out occurs in the molded product, or decomposition gas is generated during molding, making it difficult to obtain sufficient weld strength. On the other hand, if the molecular weight is larger than 20000, it is difficult to improve sufficient fluidity and weld strength.
In addition, the melt flow rate (MFR) of the olefin oligomer is preferably 50 g / 10 min or more, and more preferably 100 g / 10 min or more. If the MFR is less than 50 g / 10 min, the laser weldability tends to decrease. The MFR of the olefin oligomer is a value measured under conditions of a temperature of 190 ° C. and a load of 2.16 kg.
The content of the olefin-based oligomer is preferably 0.5 to 10 parts by mass, more preferably 2 to 10 parts by mass, and further preferably 3 to 7 parts by mass with respect to 100 parts by mass of the (A) thermoplastic polyester resin. .

The acrylic oligomer is preferably an acrylic acid or methacrylic acid alkyl ester oligomer. Such a polymer of acrylic acid or methacrylic acid alkyl ester may be other vinyl monomer, for example, α-olefin such as ethylene, propylene, butene-1, styrene, acrylonitrile, vinyl acetate, butadiene, vinyl alcohol, malee. It may contain monomer units such as acid, fumaric acid, itaconic acid or esters thereof.
Acrylic oligomers can also be obtained as commercial products. Examples of commercially available products include those manufactured by Toa Gosei Co., Ltd., trade names “Alfon (registered trademark) UP-1050”, “UH-2032”, and Soken Chemical Co., Ltd. Product names “UMB-1001”, “UMB-2005”, “UT-2001”, manufactured by ADEKA, product names “ADK STAB (registered trademark) FC-112”, “FC-113”, “LS-3” The product name “METABRENE (registered trademark) L1000” manufactured by Mitsubishi Rayon Co., Ltd. is preferred.

  The acrylic oligomer preferably has a polystyrene-equivalent mass average molecular weight of about 1000 to 10,000 as measured by GPC, preferably 1500 to 7500, and particularly preferably 2000 to 6000. If the mass average molecular weight is less than 1000, bleed out occurs in the molded product, or decomposition gas is generated during molding, making it difficult to obtain sufficient weld strength. On the other hand, if the mass average molecular weight is greater than 10,000, it is difficult to improve sufficient fluidity and weld strength.

  The content of the acrylic oligomer is preferably 0.5 to 10 parts by mass, more preferably 2 to 10 parts by mass, and further preferably 3 to 7 parts by mass with respect to 100 parts by mass of the (A) thermoplastic polyester resin. . If the content is less than 0.5 parts by mass, the effect of improving the fluidity is small, and if it exceeds 10 parts by mass, melt kneading becomes difficult, and even if kneading is possible, bleeding and gas generation during molding are likely to occur. There is a risk that dirt will adhere to the surface.

The polyfunctional compound is preferably a compound having three or more functional groups, and more preferably a polyhydric alcohol compound having three or more hydroxyl groups.
Examples of polyhydric alcohol compounds having three or more hydroxyl groups include 1,2,4-butanetriol, 1,2,5-pentanetriol, 1,2,6-hexanetriol, 1,2,3,6- Hexanetetrol, glycerin, diglycerin, triglycerin, tetraglycerin, pentaglycerin, hexaglycerin, triethanolamine, trimethylolethane, trimethylolpropane, ditrimethylolpropane, tritrimethylolpropane, 2-methylpropanetriol, 2-methyl -1,2,4-butanetriol, pentaerythritol, dipentaerythritol, tripentaerythritol, methylglucoside, sorbitol, mannitol, sucrose, 1,3,5-trihydroxybenzene, 1,2,4-trihydroxy Benzene, (poly) oxyethylene glycerol, (poly) oxypropylene glycerol, (poly) oxyethylene diglycerol, (poly) oxypropylene diglycerol, (poly) oxyethylene trimethylolpropane, (poly) oxypropylene trimethylolpropane, (Poly) oxyethylene ditrimethylolpropane, (poly) oxypropylene ditrimethylolpropane, (poly) oxyethylene pentaerythritol, (poly) oxypropylene pentaerythritol, (poly) oxyethylene dipentaerythritol, (poly) oxypropylene dipenta Examples include erythritol. Of these, pentaerythritol, trimethylolpropane, ditrimethylolpropane, and dipentaerythritol are preferable.

  As a preferred example of a compound having three or more functional groups, when the functional group is a carboxyl group, propane-1,2,3-tricarboxylic acid, 2-methylpropane-1,2,3-triscarboxylic acid, butane -1,2,4-tricarboxylic acid, butane-1,2,3,4-tetracarboxylic acid, trimellitic acid, trimesic acid, hemimellitic acid, pyromellitic acid, benzenepentacarboxylic acid, cyclohexane-1,2, 4-tricarboxylic acid, cyclohexane-1,3,5-tricarboxylic acid, cyclohexane-1,2,4,5-tetracarboxylic acid, naphthalene-1,2,4-tricarboxylic acid, naphthalene-2,5,7-tricarboxylic acid Acid, pyridine-2,4,6-tricarboxylic acid, naphthalene-1,2,7,8-tetracarboxylic acid, naphthalene-1,4,5,8- Polycarboxylic acid or acrylic acid such as tetracarboxylic acid, include polymers such as methacrylic acid, it may be used acid anhydrides thereof. Of these, propane-1,2,3-tricarboxylic acid, trimellitic acid, trimesic acid and acid anhydrides having a branched structure are preferable from the viewpoint of fluidity.

  As for content of a polyfunctional compound, 0.1-5 mass parts is preferable with respect to 100 mass parts of (A) thermoplastic polyester resins, More preferably, it is 0.1-3 mass parts, More preferably, it is 0.2-3. Part by mass.

A branched polymer can also be used as a flow modifier. A branched polymer refers to a polymer having a branched structure, and specifically refers to a polymer having a multi-branched structure. As the branched structure, a plurality of linear segments are radially branched from a central core. A star polymer, a graft polymer having a structure in which a polymer having a number of branch points is introduced into a main linear polymer chain and from which a branch polymer is introduced, and has a three-dimensional branching and branching into repeating units Examples include hyperbranched polymers having a structure, and dendrimers having a precisely controlled molecular weight distribution and degree of branching. Star polymers and hyperbranched polymers are preferable. From the viewpoint of fluidity, hyperbranched polymers are more preferable. To hyperbranched polymers are preferred.
Examples of such branched polymers include polyester-based or polyurethane-based branched polymers. Examples of commercially available hyperbranched polymers include “Borton (registered trademark)” by Perstorp.

  The content of the branched polymer is preferably 0.1 to 5 parts by mass, more preferably 0.1 to 3 parts by mass, and still more preferably 0.2 to 3 parts per 100 parts by mass of the (A) thermoplastic polyester resin. Part by mass.

  The content of these flow modifiers is 0 to 10 parts by mass with respect to 100 parts by mass of the (A) thermoplastic polyester resin. preferable. When the content is more than 10 parts by mass, the mechanical properties may be deteriorated, so 0.2 to 10 parts by mass, particularly 0.3 to 7 parts by mass is particularly preferable.

  As the stabilizer, a phosphorus stabilizer, a sulfur stabilizer and a phenol stabilizer are preferable. Examples of the phosphorus stabilizer include phosphorous acid, phosphoric acid, phosphite ester, phosphate ester, etc. Among them, organic phosphate compounds, organic phosphite compounds, or organic phosphonite compounds are preferable.

The organic phosphate compound is preferably the following general formula:
(R ⁹ O) _3-n P (═O) OH _n (4)
(In Formula (4), R < ⁹ > is an alkyl group or an aryl group, and may be the same or different. N represents an integer of 0 to 2). More preferably, R ⁹ is a long-chain alkyl acid phosphate compound having 8 to 30 carbon atoms. Specific examples of the alkyl group having 8 to 30 carbon atoms include octyl group, 2-ethylhexyl group, isooctyl group, nonyl group, isononyl group, decyl group, isodecyl group, dodecyl group, tridecyl group, isotridecyl group, tetradecyl group, hexadecyl group Group, octadecyl group, eicosyl group, triacontyl group and the like.

  Examples of the long-chain alkyl acid phosphate include octyl acid phosphate, 2-ethylhexyl acid phosphate, decyl acid phosphate, lauryl acid phosphate, octadecyl acid phosphate, oleyl acid phosphate, behenyl acid phosphate, phenyl acid phosphate, nonyl phenyl acid phosphate Acid phosphate, phenoxyethyl acid phosphate, alkoxy polyethylene glycol acid phosphate, bisphenol A acid phosphate, dimethyl acid phosphate, diethyl acid phosphate, dipropyl acid phosphate, diisopropyl acid phosphate, dibutyl acid phosphate, geo Chill acid phosphate, di-2-ethylhexyl acid phosphate, dioctyl acid phosphate, dilauryl acid phosphate, distearyl acid phosphate, diphenyl acid phosphate, and a bis-nonylphenyl acid phosphate, or the like. Among these, octadecyl acid phosphate is preferable.

The organic phosphite compound is preferably the following general formula:
R < ¹⁰ > O-P (OR < ¹¹ >) (OR < ¹² >) ... (5)
(In the formula ^(5), R ^{10, R 11} and ^{R 12} are each a hydrogen atom, an alkyl group or an aryl group having 6 to 30 carbon atoms having 1 to 30 carbon ^atoms, the R ^{10, R 11} and ^{R 12} At least one of which is an aryl group having 6 to 30 carbon atoms.).

  Examples of the organic phosphite compound include triphenyl phosphite, tris (nonylphenyl) phosphite, dilauryl hydrogen phosphite, triethyl phosphite, tridecyl phosphite, tris (2-ethylhexyl) phosphite, and tris (tridecyl). ) Phosphite, tristearyl phosphite, diphenyl monodecyl phosphite, monophenyl didecyl phosphite, diphenyl mono (tridecyl) phosphite, tetraphenyldipropylene glycol diphosphite, tetraphenyltetra (tridecyl) pentaerythritol tetraphosphite Hydrogenated bisphenol A phenol phosphite polymer, diphenyl hydrogen phosphite, 4,4′-butylidene-bis (3-methyl-6-t rt-butylphenyldi (tridecyl) phosphite), tetra (tridecyl) 4,4′-isopropylidenediphenyldiphosphite, bis (tridecyl) pentaerythritol diphosphite, bis (nonylphenyl) pentaerythritol diphosphite, di Lauryl pentaerythritol diphosphite, distearyl pentaerythritol diphosphite, tris (4-tert-butylphenyl) phosphite, tris (2,4-di-tert-butylphenyl) phosphite, hydrogenated bisphenol A pentaerythritol phosphite Phytopolymer, bis (2,4-di-tert-butylphenyl) pentaerythritol diphosphite, bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite Phosphite, 2,2'-methylenebis (4,6-di -tert- butylphenyl) octyl phosphite, bis (2,4-dicumylphenyl) pentaerythritol diphosphite and the like. Among these, bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite is preferable.

The organic phosphonite compound is preferably the following general formula:
R ¹³ -P (OR ¹⁴ ) (OR ¹⁵ ) (6)
(In the formula ^(6), R ^{13, R 14} and ^{R 15} are each a hydrogen atom, an alkyl group or an aryl group having 6 to 30 carbon atoms having 1 to 30 carbon ^atoms, R ^{13, R 14} and ^{R 15} At least one of which is an aryl group having 6 to 30 carbon atoms.).

  Examples of the organic phosphonite compound include tetrakis (2,4-di-iso-propylphenyl) -4,4′-biphenylenediphosphonite, tetrakis (2,4-di-n-butylphenyl) -4,4′-biphenyl. Range phosphonite, tetrakis (2,4-di-tert-butylphenyl) -4,4'-biphenylene diphosphonite, tetrakis (2,4-di-tert-butylphenyl) -4,3'-biphenylene diphospho Knight, tetrakis (2,4-di-tert-butylphenyl) -3,3'-biphenylenediphosphonite, tetrakis (2,6-di-iso-propylphenyl) -4,4'-biphenylenediphosphonite, Tetrakis (2,6-di-n-butylphenyl) -4,4′-biphenylenediphosphonite, tetrakis (2, -Di-tert-butylphenyl) -4,4'-biphenylenediphosphonite, tetrakis (2,6-di-tert-butylphenyl) -4,3'-biphenylenediphosphonite, and tetrakis (2,6- And di-tert-butylphenyl) -3,3′-biphenylenediphosphonite.

  As the sulfur stabilizer, any conventionally known sulfur atom-containing compound can be used, and among these, thioethers are preferred. Specifically, for example, didodecylthiodipropionate, ditetradecylthiodipropionate, dioctadecylthiodipropionate, pentaerythritol tetrakis (3-dodecylthiopropionate), thiobis (N-phenyl-β-naphthylamine) ), 2-mercaptobenzothiazole, 2-mercaptobenzimidazole, tetramethylthiuram monosulfide, tetramethylthiuram disulfide, nickel dibutyldithiocarbamate, nickel isopropylxanthate, trilauryltrithiophosphite. Among these, pentaerythritol tetrakis (3-dodecylthiopropionate) is preferable.

  Examples of the phenol-based stabilizer include pentaerythritol tetrakis (3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate), octadecyl-3- (3,5-di-tert-butyl-4) -Hydroxyphenyl) propionate, thiodiethylenebis (3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate), pentaerythritol tetrakis (3- (3,5-di-neopentyl-4-hydroxyphenyl) ) Propionate) and the like. Among these, pentaerythritol tetrakis (3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate), octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) ) Propionate is preferred.

  One type of stabilizer may be contained, or two or more types may be contained in any combination and ratio.

  The content of the stabilizer is preferably 0.001 to 1 part by mass with respect to 100 parts by mass of the (A) thermoplastic polyester resin. When the content of the stabilizer is less than 0.001 part by mass, it is difficult to expect an improvement in the thermal stability and compatibility of the resin composition, and a decrease in molecular weight and a deterioration in hue during molding are likely to occur. When it exceeds, it will become excess amount and there exists a tendency for generation | occurrence | production of silver and a hue deterioration to occur further easily. The content of the stabilizer is more preferably 0.001 to 0.7 parts by mass, and still more preferably 0.005 to 0.5 parts by mass.

  As the mold release agent, known mold release agents usually used for polyester resins can be used. Among them, one or more mold release agents selected from polyolefin compounds, fatty acid ester compounds, and silicone compounds are used. preferable.

  Examples of the polyolefin compound include compounds selected from paraffin wax and polyethylene wax. Among them, those having a mass average molecular weight measured by GPC of 700 to 10000, more preferably 900 to 8000 are preferable. In addition, a modified polyolefin compound in which a hydroxyl group, a carboxyl group, a hydroxyl group, an epoxy group or the like is introduced into the side chain is particularly preferable.

  Examples of the fatty acid ester compounds include fatty acid esters such as glycerin fatty acid esters, sorbitan fatty acid esters, and pentaerythritol fatty acid esters, and partially saponified products thereof. Among them, carbon number is 11 to 28, preferably carbon number 17 Fatty acid esters composed of ~ 21 fatty acids are preferred. Specific examples include glycerol monostearate, glycerol monobehenate, glycerol dibehenate, glycerol-12-hydroxy monostearate, sorbitan monobehenate, pentaerythritol distearate, pentaerythritol tetrastearate and the like.

  Moreover, as a silicone type compound, the compound modified | denatured from points, such as compatibility with a polyester resin, is preferable. Examples of the modified silicone oil include silicone oil in which an organic group is introduced into the side chain of polysiloxane, silicone oil in which an organic group is introduced into both ends and / or one end of polysiloxane, and the like. Examples of the organic group to be introduced include an epoxy group, an amino group, a carboxy group, a carbinol group, a methacryl group, a mercapto group, and a phenol group, and preferably an epoxy group. As the modified silicone oil, a silicone oil in which an epoxy group is introduced into the side chain of polysiloxane is particularly preferable.

  It is preferable that content of a mold release agent is 0.05-2 mass parts with respect to 100 mass parts of (A) thermoplastic polyester resin. If the amount is less than 0.05 parts by mass, the surface property tends to decrease due to poor mold release at the time of melt molding, while if it exceeds 2 parts by mass, the kneading workability of the resin composition decreases, Cloudiness may be seen on the surface of the molded product. The content of the release agent is preferably 0.07 to 1.5 parts by mass, more preferably 0.1 to 1.0 parts by mass.

  Moreover, the resin composition of this invention can contain thermoplastic resins other than (A) thermoplastic polyester resin in the range which does not impair the effect of this invention. Specific examples of the other thermoplastic resins include polyacetal resins, polyphenylene oxide resins, polyphenylene sulfide resins, polysulfone resins, polyether sulfone resins, polyetherimide resins, polyether ketone resins, polyolefin resins, and the like. It is done.

As a manufacturing method of the resin composition of this invention, it can carry out in accordance with the conventional method of resin composition preparation. Usually, the components and various additives added as desired are mixed together and then melt-kneaded in a single or twin screw extruder. Further, the resin composition of the present invention can also be prepared without mixing each component in advance or by mixing only a part of the components in advance and supplying them to an extruder using a feeder and melt-kneading them. Further, a master batch is prepared by melt-kneading a part of a thermoplastic polyester resin and a part of other components, and then the remaining polyester resin and other ingredients are blended and melt-kneaded. May be.
In addition, when using fibrous reinforcement fillers, such as glass fiber, it is also preferable to supply from the side feeder in the middle of the cylinder of an extruder.

  The heating temperature at the time of melt kneading can be appropriately selected from the range of usually 220 to 300 ° C. If the temperature is too high, decomposition gas is likely to be generated, which may cause opacity. Therefore, it is desirable to select a screw configuration in consideration of shear heat generation. In order to suppress decomposition during kneading or molding in the subsequent process, it is desirable to use an antioxidant or a heat stabilizer.

[Laser welded compact]
The manufacturing method of a molded object is not specifically limited, The molding method generally employ | adopted about the polyester resin composition can be employ | adopted arbitrarily. For example, injection molding method, ultra-high speed injection molding method, injection compression molding method, two-color molding method, hollow molding method such as gas assist, molding method using heat insulating mold, rapid heating mold were used. 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, Examples thereof include blow molding, and injection molding is particularly preferable.

The laser welding resin composition of the present invention is preferably adjusted so that the incidence rate K is in the range of 20 to 80%.
The incident rate K is an incident rate with respect to a laser beam having a wavelength of 940 nm, converted into 1 mm thickness of a molded product,
It is defined as incident rate K (%) = 100−transmittance−reflectance.

The molded body obtained by molding the laser welding resin composition of the present invention has an incidence rate K of preferably 20 to 80%, more preferably 40 to 70%, and particularly preferably 45 to 65%. As a result, the amount of laser light transmitted and the amount of laser light absorbed are adjusted, so that two types of molded products composed of a laser light-transmitting resin and a molded body composed of a laser light-absorbing resin are used as in conventional laser welding. It is not necessary to use it, and it becomes possible to provide a polyester-based laser-welded molded body that can be laser-welded with only one type of resin material. In particular, the effect of the present invention is remarkable when welding welds made of the same kind of resin material are welded together.
The shape of the laser welded molded body is arbitrary, and it may be a deformed extruded product (bar, pipe, etc.) that is used for welding by abutting the end, and a current-carrying part that requires particularly high waterproofness and airtightness, A metal-inserted molded product used for electronic parts and the like is also preferable.

[Laser welded body]
In the laser welding resin composition of the present invention, the incidence rate K is preferably adjusted to a range of 20 to 80% (incidence rate K with respect to 940 nm laser light, 1 mm thickness conversion). For this reason, as described above, it is not necessary to use two types of a molded body made of a laser light-transmitting resin and a molded body made of a laser light-absorbing resin, and the laser light has a large penetration depth, and therefore a large melting Since the depth can be ensured, sufficiently high welding strength can be achieved not only by superposition welding but also by butt welding of the end portions of the laser welding molded body, which has not been possible until now. In addition, even when a gap is generated in the joining portion due to sink marks or warpage during molding, the gap is 0.1 mm or more, preferably 0.2 mm or more, more preferably 0.5 mm or more, particularly 1 mm. Even in the above case, laser welding is possible.

  The type of laser light to be irradiated is arbitrary as long as it is near-infrared laser light. YAG (yttrium, aluminum, garnet crystal) laser (wavelength 1064 nm), LD (laser diode) laser (wavelength 808 nm, 820 nm, 840 nm, 880 nm) , 940 nm) and the like can be preferably used.

  The shape, size, thickness, etc. of the welded body that has been laser-welded are arbitrary. Applications of the welded body include parts for transportation equipment such as automobiles, parts for electrical and electronic equipment, parts for industrial machinery, and other consumer parts. Is preferred.

Preferred examples of the laser welding method include butt welding and superposition welding.
In the butt welding, as shown in FIG. 1, the two molded bodies 1 and 2 are butted and irradiated with the laser beam 4 while being scanned, so that a welded portion 5 is generated, thereby forming a laser welded body.
As shown in FIG. 2, the superposition welding is performed by superimposing and scanning the two molded bodies 1 and 2 and irradiating the laser beam 4 while scanning to form a welded portion 5, thereby forming a laser welded body. .

  The molded body obtained with the colored resin composition of the present invention is abutted and laser welded, so that the obtained laser welded body has a considerably improved tensile strength and is required for the laser welded body. Satisfies strength. Also, considering the laser welding conditions, it can be seen that the allowable range of the amount of energy by the laser beam has a significantly wide range, and such a compact that can meet such a wide range of laser welding requirements has a complicated structure. It is possible to provide laser welding with high practicality for welding of molded bodies of the above, welding of molded bodies having changed thickness, and the like.

  EXAMPLES Next, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.

  Below, the manufacture example of the comparative colorant example 1 used for the manufacture example of the colorant examples 1-3 used for the Example and the comparative example is shown.

(Production Example 1: Production of Colorant Example 1)
1: 1 type azomethine nickel complex (Compound Example 1 in Table 1 above, ie, R ^{1 to} R ⁹ = H, CI Solvent Brown 53) 0.38 parts by mass and triphenylmethane dye 1 (CI Solvent) Blue 23) 0.22 part by mass was placed in a blender and stirred for 5 hours to obtain 0.60 part by mass of Colorant Example 1.

(Production Example 2: Production of Colorant Example 2)
In Production Example 1, the blending composition was 1: 1 type azomethine nickel complex (CI Solvent Brown 53) 1.14 parts by mass and triphenylmethane dye 1 (CI Solvent Blue 23) 0.66 parts by mass. In place of 1.80 parts by mass of Colorant Example 2 was obtained.
(Production Example 3: Production of Colorant Example 3)
In Production Example 1, the blend composition was 1.90 parts by weight of a 1: 1 type azomethine nickel complex (CI Solvent Brown 53) and 1.10 parts by weight of triphenylmethane dye 1 (CI Solvent Blue 23). Instead of the above, 3.00 parts by mass of Colorant Example 3 was obtained.

(Comparative Production Example 1: Production of Comparative Colorant Example 1)
In Production Example 1, the compounding composition was 0.66 parts by mass of triphenylmethane dye 1 (CI Solvent Blue 23) and 0.57 parts by mass of perinone dye 1 (maximum absorption wavelength 472 nm CI Solvent Red 179). And anthraquinone dye 3 (maximum absorption wavelength 446 nm CI Solvent Yellow 163) was changed to 0.57 parts by mass to obtain 1.80 parts by mass of Comparative Colorant Example 1.

  Examples 1 to 3 were performed using the colorant examples 1 to 3 produced above to produce molded body examples 1 to 3. Moreover, Comparative Example 1 was performed using Comparative Colorant Example 1 that was not applied to the present invention, and Comparative Molded Example 1 was obtained.

(Example 1: Production of molded body example 1)
600 parts by mass of polybutylene terephthalate resin (manufactured by Mitsubishi Engineering Plastics, Novaduran (registered trademark) 5010G30X4), nigrosine (manufactured by Orient Chemical Industry Co., Ltd., NUBIAN (registered trademark) BLACK TH-807) 0.06 parts by mass, and coloring Preparation Example 11 0.60 part by mass was placed in a stainless steel tumbler and stirred and mixed for 1 hour. The resulting mixture was molded by an ordinary method using an injection molding machine Si-50 at a cylinder temperature of 260 ° C. and a mold temperature of 80 ° C., and a black molded body example 1 having a length of 80 mm × width 20 mm × thickness 2 mm Two pieces (molded body example 1-1 and molded body example 1-2) were produced.
Furthermore, as a test piece for measuring the incidence rate, a black molded body example 1K having a two-stage shape of 80 mm in length, 50 mm in width, 1.5 mm in thickness and 1 mm was produced.
The transmittance, reflectance, and incidence rate K were as follows.
Transmittance: 24.5%, reflectivity: 30.0%, incidence K: 45.5%

(Calculation method of incidence rate K)
The calculation method of the incidence rate K (%) is as follows.
Using a spectrophotometer (manufactured by JASCO Corporation, V-570), the transmittance and reflectance at 940 nm were measured for an example of a measurement piece molded body for incidence rate, and the incidence rate K (unit:%) from the following formula. Was calculated.
Incident rate K (%) = 100−transmittance−reflectance

(Example 2: Production of molded body example 2)
600 parts by mass of polybutylene terephthalate resin (Novaduran 5010G30X4), 0.06 parts by mass of nigrosine (NUBIAN BLACK TH-807), and 1.8 parts by mass of Colorant Example 2 were placed in a stainless steel tumbler and mixed with stirring for 1 hour. . The obtained mixture was molded by an ordinary method using an injection molding machine Si-50 at a cylinder temperature of 260 ° C. and a mold temperature of 80 ° C., and a black molded body example 2 having a length of 80 mm × width of 20 mm × thickness of 2 mm was obtained. Two (molded body example 2-1 and molded body example 2-2) were produced.
Furthermore, as a test piece for measuring the incidence rate, a black molded body example 2K having a two-stage shape of 80 mm in length, 50 mm in width, 1.5 mm in thickness and 1 mm was produced.
The transmittance, reflectance, and incidence rate K were as follows.
Transmittance: 22.4%, Reflectance: 27.8%, Incidence K: 49.8%

(Example 3: Production of molded body example 3)
600 parts by weight of polybutylene terephthalate resin (Novaduran 5010G30X4), 0.06 parts by weight of nigrosine (NUBIAN BLACK TH-807), and 3.0 parts by weight of Colorant Example 3 were placed in a stainless steel tumbler and mixed with stirring for 1 hour. . The resulting mixture was molded by an ordinary method using an injection molding machine Si-50 at a cylinder temperature of 260 ° C. and a mold temperature of 80 ° C., and a black molded body example 3 having a length of 80 mm × width of 20 mm × thickness of 2 mm. (Molded body example 3-1 and molded body example 3-2) were produced.
Furthermore, as a test piece for incidence rate measurement, a black molded body example 3K having a two-stage shape of 80 mm in length, 50 mm in width, 1.5 mm in thickness and 1 mm was produced.
Transmittance: 18.8%, Reflectance: 24.4%, Incidence K: 56.8%

(Comparative Example 1: Production of Comparative Molded Body Example 1)
600 parts by mass of polybutylene terephthalate resin (Novaduran 5010G30X4), 0.06 parts by mass of nigrosine (: NUBIAN BLACK TH-807), and 0.6 parts by mass of Comparative Colorant Example 1 are placed in a stainless steel tumbler and stirred for 1 hour. Mixed. The resulting mixture was molded by an ordinary method using an injection molding machine Si-50 at a cylinder temperature of 260 ° C. and a mold temperature of 80 ° C., and a black comparative molded body example having a length of 80 mm × width of 20 mm × thickness of 2 mm. 1 (Comparative molded body example 1-1, Comparative molded body example 1-2) was produced.
Furthermore, as a test piece for measuring the incidence rate, a black comparative molded body example 1K having a stepped shape of 80 mm in length, 50 mm in width, 1.5 mm in thickness, and 1 mm was prepared.
Transmittance: 24.8%, reflectance: 30.7%, incidence K: 44.5%

  Using the molded body example 1, molded body example 2, molded body example 3 and comparative molded body example 1 produced as described above, a laser welded body in which the molded bodies were butted and welded was manufactured, and the obtained laser welded body was evaluated by the following method. did. The results are shown in Tables 2 and 3.

(Example A1)
Two molded body examples 2 (molded body 2-1 and molded body 2-2) are brought into contact with each other while being abutted as shown in FIG. 1 and output along the interface between the abutted molded bodies 1 and 2. When a laser beam 4 from a 50 W diode laser [wavelength: 940 nm continuous] (manufactured by Fine Devices) was scanned at a scanning speed of 11 mm / sec for 15 mm and irradiated, an integrated laser weld was obtained.

(Example A2)
Two molded body examples 3 (molded body 3-1 and molded body 3-2) are brought into contact with each other while being abutted as shown in FIG. 1 and output along the interface between the abutted molded bodies 1 and 2. When a laser beam 4 from a 50 W diode laser [wavelength: 940 nm continuous] (manufactured by Fine Devices) was scanned at a scanning speed of 11 mm / sec for 15 mm and irradiated, an integrated laser weld was obtained.

(Example A3)
Instead of the two molded body examples 2 (molded body 2-1 and molded body 2-2), the two molded body examples 1 (molded body 1-1 and molded body 1-2), the scanning speed of the laser beam is changed. Except for changing to 6 mm / sec, the same operation as in Example A1 was performed to obtain an integrated laser welded body.

(Example A4)
Except that the scanning speed of the laser beam was changed to 6 mm / sec, the same operation as in Example A1 was performed to obtain an integrated laser welded body.

(Comparative Example A1)
Two comparative molded body examples 1 (comparative molded body 1-1 and comparative molded body 1-2) are brought into contact with each other while being abutted as shown in FIG. 1, and along the interface between the abutted molded bodies 1 and 2. When the laser beam 4 by a diode laser with a power of 50 W [wavelength: 940 nm continuous] (manufactured by Fine Devices) is scanned at a scanning speed of 11 mm / sec for 15 mm and irradiated, an integrated laser welded body is obtained. Obtained.

(Comparative Example A2)
Except for changing the scanning speed of the laser beam to 6 mm / sec, the same operation as in Comparative Example A1 was performed to obtain an integrated laser welded body.

The details of the laser welding conditions are as follows.
Laser welding machine: FD-200 (50W machine) manufactured by Fine Devices
Output: 50W (setting)
Spot diameter: 1mmφ
Scanning speed: Scanning speed described in Table 2 or Table 3 (mm / sec)
Scanning distance: 15mm

About the obtained laser welded body, in accordance with JIS K7161-1994, the test speed is 10 mm / min in the longitudinal direction of the welded body (direction in which the welded part is separated) with a tensile tester (manufactured by Shimadzu Corporation, AG-50kNE). A tensile test was conducted to measure the tensile strength (unit: N).
The results are shown in Tables 2 and 3.

  As the results shown in Table 2 and Table 3 above, the laser welds obtained in Example A1 to Example A4 have higher tensile strength than the laser welds obtained in Comparative Examples A1 and A2. In practice, sufficient laser welding strength was obtained.

  The resin composition for laser welding of the present invention has extremely excellent laser welding processability in addition to high colorability and heat resistance. Therefore, since the resin composition of the present invention can be suitably and widely applied to automobile parts, electrical / electronic equipment parts, and other materials, industrial applicability is very high.

Claims (9)

It is a resin composition used for welding by laser light, and (A) 0.0005 to 0.5 parts by mass of nigrosine and (C) 1 represented by the formula (1) with respect to 100 parts by mass of the thermoplastic polyester resin. A resin composition for laser welding, comprising 0.01 to 2 parts by mass of a colorant containing at least a 1-type azomethine nickel complex.
In Expression ^(1), R 1 ~R ⁸ are the same or different, a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, an alkoxy group having 1 to 18 carbon atoms, a carboxy group, hydroxy group, an amino group, an alkylamino A group, a nitro group or a halogen atom. ]   (C) The resin composition for laser welding according to claim 1, wherein the colorant further contains an anthraquinone dye or a triphenylmethane dye.   (A) The resin composition for laser welding according to claim 1 or 2, wherein the main component of the thermoplastic polyester resin is a polybutylene terephthalate resin. The laser welding resin composition according to any one of claims 1 to 3, wherein the 1 mm-thick molded plate made of the resin composition has an incidence K of 20 to 80% with respect to 940 nm laser light.
However, the incident rate K (%) = 100−transmittance−reflectance.   The laser welding molded object which consists of a resin composition for laser welding of any one of Claims 1-4.   A laser welded product of the molded product according to claim 5.   The laser welded body according to claim 6, wherein a gap between the molded bodies when the welded body is welded is at least 0.1 mm in at least a part of the welded portion.   The laser welded body according to claim 6 or 7, wherein the molded bodies are butt-welded to each other.   The laser welded body according to claim 6 or 7, wherein the molded bodies are laminated and welded together.