JP2013053316A - Thermoplastic resin composition for laser welding, molding, method of manufacturing molding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermoplastic resin composition in which mechanical strength is excellent, and that is excellent in laser welding properties.SOLUTION: The thermoplastic resin composition for laser welding is made by combining 10-150 pts.wt of a glass fiber (B) in which a cross section that is vertical to a fiber length direction has a flat shape in which the flat rate by the following formula is at least 1.5, based on 100 pts.wt of a thermoplastic resin (A) including at least one polyester resin or polyamide resin. The flat rate can be obtained by dividing the major axis (D2) of the cross section of the glass fiber by the minor axis (D1) of the cross section of the glass fiber.

Description

  The present invention relates to a thermoplastic resin composition for laser welding. In particular, the present invention relates to a laser welding thermoplastic resin composition that can be firmly bonded to other resin members by laser welding.

In recent years, thermoplastic resin products that can be reduced in weight have been used for structural parts in the fields of automobiles and electronic / electrical equipment in place of metal. Examples of the thermoplastic resin used in these structural parts include polyester resins, polyamide resins, and polycarbonate resins. Among these, polyester resins and polyamide resins typified by polybutylene terephthalate resins and polyethylene terephthalate resins are used. Because of its excellent mechanical properties, electrical properties, heat resistance, dimensional stability, and other physical and chemical properties, it is widely used in vehicle parts, electrical / electronic equipment parts, precision equipment parts, and the like. In recent years, polybutylene terephthalate resin is used in products that seal electrical circuit parts such as vehicle electrical parts (control units, etc.), various sensor parts, connector parts, etc. It has been developed in products having a hollow portion such as a manifold.
In products that seal these electric circuit parts or products that have hollow parts, it may be necessary to weld or seal multiple members, and various welding and sealing techniques such as adhesive welding, vibration welding, ultrasonic Welding, hot plate welding, injection welding, laser welding techniques, etc. are used.

  However, the adhesion by the adhesive has a problem of environmental load such as contamination of the surroundings in addition to the time loss until curing. Ultrasonic welding, hot plate welding, and the like have been pointed out as problems such as damage to products due to vibration and heat, and post-treatment required due to generation of wear powder and burrs. In addition, injection welding often requires a special mold or molding machine, and further has a problem that it cannot be used unless the fluidity of the material is good.

  On the other hand, laser welding is a welding method in which a resin member that is transmissive (also referred to as non-absorbing or weakly absorbing) to laser light and a resin member that absorbs laser light are brought into contact with each other for welding. is there. This is a method of irradiating a bonding surface with laser light from the side of the transmissive resin member, and melting and bonding the resin member exhibiting absorbency for forming the bonding surface with the energy of the laser beam. Laser welding is recently attracting attention because it is non-pressure welded and does not generate wear powder or burrs and has little damage to the product.

  In order to solve the above problem, there is a method of widening the welding condition width by controlling the melting point using a polybutylene terephthalate copolymer (Patent Document 1). With this method alone, the improvement in transmittance is small, and improvement in product wall thickness design margin cannot be expected. Moreover, the method of mix | blending an amorphous resin and an elastomer with a polybutylene terephthalate-type resin is disclosed (patent documents 2 and 3). Although this method may improve the transmittance, there is a problem that the transmittance is likely to vary depending on the blending and molding conditions.

It is a welding material for laminating the first resin member and the second resin member and irradiating laser light from the first resin member side to weld them together, and is weakly absorbing to the laser light. A laser welding material comprising a certain first resin member and a second resin member that is absorbable with laser light is described. As a specific example of the first resin member that is weakly absorbent to laser light, a resin composition in which a modified ethylene / α-olefin copolymer is blended with polyamide 6 is absorbent to laser light. As a specific example of the second resin member, a resin composition in which 0.3% by weight of carbon black is blended with polyamide 6 is described (Patent Document 4).
However, the resin composition of Patent Document 4 has insufficient mechanical strength and rigidity, and cannot be used for applications that require these performances.

When used for applications that require high mechanical strength and rigidity, these properties can be improved by adding fillers such as glass fibers and glass flakes. However, when fillers such as glass fibers and glass flakes are added, there is a problem that the transmittance of the laser beam is lowered, and the content of the filler is limited in the member on the laser transmission side.
As a resin composition for laser welding containing a filler, a resin composition containing 10 to 90 parts by weight of a polycarbonate resin and 10 to 90 parts by weight of a filler is proposed with respect to 100 parts by weight of a polyamide resin (Patent Document). 5).

  However, even the resin composition described in Patent Document 5 has insufficient laser permeability and low laser weldability. In the examples, the blending amount of the filler with respect to the resin component of the polyamide resin and the polycarbonate resin is low (the blending amount of the filler is 11 parts by weight when converted to 100 parts by weight of the resin component), and the mechanical strength and If the filler content is increased to improve the rigidity, problems such as a decrease in laser transmission and appearance of the molded product remain.

  On the other hand, in Patent Document 6, by making the cross-sectional shape of the glass fiber, which is representative of the reinforcing fiber, flat, the specific surface area is increased as compared with the glass fiber having a circular cross section, and the adhesion effect with the matrix resin composition is increased. Moreover, it is shown that the mechanical strength is improved by increasing the fiber length in the molded body (average fiber length is 0.47 mm in the case of a circular cross-sectional shape, and 0.57 mm in a cross-sectional shape of eyebrows). Has been. However, there is no description about the relationship between the cross-sectional shape of the reinforcing fiber and the laser weldability.

  Further, in order to reduce the anisotropy of the shrinkage rate generated when the reinforcing fiber is blended with the thermoplastic resin, the ratio D2 / D1 of the long diameter D2 to the short diameter D1 of the flat cross section, specifically, the cross section of the glass fiber. There has been proposed a thermoplastic resin composition in which a glass fiber powder having an A of 1.2 or more is blended as a reinforcing material (Patent Document 7). However, there is no description that predicts the relationship between the cross-sectional shape of the reinforcing material and the laser weldability.

  A laser welding resin composition in which an inorganic filler is blended with a specific polyarylene sulfide resin has been proposed (Patent Document 8). According to claim 4 of the cited document, for the purpose of reducing warpage deformation, the long diameter (longest straight line distance) and the short diameter (longest straight line in the direction perpendicular to the long diameter) are used as the inorganic filler. It is shown that a glass fiber mainly composed of E glass having a flat cross-sectional shape with a distance) ratio of 1.3 to 10 is blended. However, even when the resin composition of Patent Document 7 is used, the laser welding strength is not sufficient.

Japanese Patent No. 3510817 Japanese Patent Laid-Open No. 2003-292752 JP 2004-315805 A JP 2004-148800 A JP 2006-2731992 A Japanese Patent Laid-Open No. 62-268612 Japanese Patent Laid-Open No. 7-18186 JP 2005-336229 A

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a thermoplastic resin composition for laser welding having excellent mechanical strength and excellent laser welding characteristics. It is another object of the present invention to provide a method for manufacturing a molded product including a step of welding using laser light and a molded product firmly bonded by the manufacturing method.

  As a result of intensive studies to solve the above problems, the present inventors have blended glass fibers whose cross section perpendicular to the fiber length direction is a flat shape, so that the mechanical strength and transmission of the resin molded product are obtained. It has been found that a thermoplastic resin composition for laser welding having an improved rate and excellent laser welding characteristics can be obtained, and as a result, a molded product firmly bonded by laser welding can be obtained.

The present invention has been completed based on the above findings, and the gist thereof is as follows.
(1) The cross section perpendicular to the fiber length direction is a flat shape having a flatness ratio of 1.5 or more according to the following formula with respect to 100 parts by weight of the thermoplastic resin (A) containing at least one polyester resin or polyamide resin. A thermoplastic resin composition for laser welding, comprising 10 to 150 parts by weight of glass fiber (B).
Flatness ratio = major axis (D2) of glass fiber section / minor axis (D1) of glass fiber section
(2) The thermoplastic resin composition for laser welding according to (1), wherein the flatness of the glass fiber (B) is 1.5 to 10.
(3) The thermoplastic resin composition for laser welding according to (1), wherein the flatness of the glass fiber (B) is 2.5 to 6.
(4) The laser welding thermoplastic resin composition according to any one of (1) to (3), wherein the cross-sectional shape of the glass fiber (B) is an oval, an ellipse, or a rectangle.
(5) The thermoplastic resin composition for laser welding according to any one of (1) to (4), wherein the polyester resin is a polybutylene terephthalate resin.
(6) The laser welding thermoplastic resin composition according to (5), wherein the polybutylene terephthalate resin is obtained using a titanium compound as a catalyst, and the concentration of contained titanium is 80 ppm or less as titanium atoms.
(7) The thermoplastic resin composition for laser welding according to (5) or (6), wherein the terminal carboxyl group concentration of the polybutylene terephthalate resin is 40 eq / ton or less.
(8) The thermoplastic resin composition for laser welding according to any one of (1) to (7), wherein at least one monomer constituting at least one polyamide resin contains an aromatic ring.
(9) The polyamide resin contains, as a structural unit (a), at least one selected from a salt composed of an aliphatic diamine and an aromatic dicarboxylic acid and a salt composed of an aromatic diamine and an aliphatic dicarboxylic acid. The thermoplastic resin composition for laser welding according to any one of to (8).
(10) The thermoplastic resin composition for laser welding according to (9), wherein the structural unit (a) is 30 mol% or more of all structural units of the polyamide resin.
(11) The polyamide resin contains at least one selected from the salt consisting of hexamethylenediamine and terephthalic acid and / or isophthalic acid, and the salt consisting of xylylenediamine and adipic acid as the structural unit (a). The thermoplastic resin composition for laser welding according to any one of (1) to (10).
(12) The thermoplastic resin composition for laser welding according to any one of (1) to (11), further comprising a colorant (C).
(13) The thermoplastic resin composition for laser welding according to any one of (1) to (12), which is used for a member on a laser transmission side.
(14) A member made of the laser-welded reinforced thermoplastic resin composition (I) according to any one of (1) to (13) and a member made of the resin composition (II) having laser absorptivity, A molded article formed by welding by irradiating a laser beam from the member side made of the composition (I).
(15) A member made of the thermoplastic resin composition (I) for laser welding according to any one of (1) to (13) and a member made of the thermoplastic resin composition (II) having laser absorptivity, The manufacturing method of the molded article including the process of irradiating and welding a laser beam from the member side which consists of resin composition (I).

  According to the present invention, it is possible to provide a thermoplastic resin composition having good mechanical strength and excellent laser welding characteristics such as laser transmission. Further, by using the laser welding thermoplastic resin composition of the present invention, it is possible to provide a molded article having good mechanical strength and firmly bonded by laser welding. Such a molded product is widely used industrially in the vehicle field, the electric / electronic field, the machine field, and the like, and its utility value is extremely high.

FIG. 1 is a schematic view showing a laser welding strength measuring method in an embodiment of the present invention. FIG. 2 is an explanatory diagram of an example of an esterification (or transesterification) reaction step in (A1) PBT resin production. FIG. 3 is an explanatory diagram of an example of a polycondensation step in (A1) PBT resin production.

  Hereinafter, the contents of the present invention will be described in detail. 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.

<Thermoplastic resin (A)>
The thermoplastic resin (A) in the present invention is a thermoplastic resin containing at least one polyester resin or polyamide resin. Other types of thermoplastic resins may be mixed with the polyester resin or polyamide resin, and the resin to be mixed may be either a crystalline thermoplastic resin or an amorphous thermoplastic resin.
Examples of the crystalline thermoplastic resin include polyacetal resins and polyolefin resins. Examples of the amorphous thermoplastic resin include a polycarbonate resin, a polyphenylene ether resin, and an aromatic vinyl compound polymer. Among these, those having a high transmittance in a wavelength region of a laser usually used for thermoplastic resin welding (for example, YAG laser is 1064 nm and semiconductor laser is 655 to 980 nm) are preferable. When mixing other resin with a polyester resin or a polyamide resin, 1-200 weight part is preferable with respect to 100 weight part of polyamide resin or polyester resin, 10-100 weight part is more preferable, and 20-80 weight part is further preferable.

(Polyester resin)
As the polyester resin used in the present invention, known polyester resins can be widely used. The polyester resin is preferably a polyester resin composed of a dicarboxylic acid or a derivative thereof and a diol.

As the dicarboxylic acid or derivative thereof, aromatic dicarboxylic acid, alicyclic dicarboxylic acid, and aliphatic dicarboxylic acid, and esters of these lower alkyls or glycols are preferred, and aromatic dicarboxylic acids or their lower alkyls (for example, C1-C4) or an ester of glycol is more preferable, and terephthalic acid or a lower alkyl ester thereof is more preferable.
Aromatic dicarboxylic acids include terephthalic acid, phthalic acid, isophthalic acid, 4,4′-diphenyldicarboxylic acid, 4,4′-diphenyl ether dicarboxylic acid, 4,4′-benzophenone dicarboxylic acid, 4,4′-diphenoxy. Preferred examples include ethanedicarboxylic acid, 4,4′-diphenylsulfonedicarboxylic acid, and 2,6-naphthalenedicarboxylic acid.
Preferred examples of the alicyclic dicarboxylic acid include 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, and 1,4-cyclohexanedicarboxylic acid.
Preferred examples of the aliphatic dicarboxylic acid include malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid and sebacic acid.
Two or more of these dicarboxylic acids or derivatives thereof may be used in combination.

As the diol, aliphatic diol, alicyclic diol and aromatic diol are preferable.
The aliphatic diol is preferably an aliphatic diol having 2 to 20 carbon atoms, such as ethylene glycol, 1,4-butanediol, diethylene glycol, polyethylene glycol, 1,2-propanediol, 1,3-propanediol, Preferable examples include polypropylene glycol, polytetramethylene glycol, dibutylene glycol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol and 1,8-octanediol.
The alicyclic diol is preferably an alicyclic diol having 2 to 20 carbon atoms, such as 1,2-cyclohexanediol, 1,4-cyclohexanediol, 1,1-cyclohexanedimethylol and 1,4-cyclohexane. A preferred example is dimethylol.
The aromatic diol is preferably an aromatic diol having 6 to 14 carbon atoms, such as xylylene glycol, 4,4′-dihydroxybiphenyl, 2,2-bis (4-hydroxyphenyl) propane and bis (4- Hydroxyphenyl) sulfone can be mentioned as a preferred example.
Two or more of these diols may be used in combination.

  The polyester resin used in the present invention may have a hydroxycarboxylic acid, a monofunctional component, and / or a trifunctional or higher polyfunctional component. Preferred examples of the hydroxycarboxylic acid include lactic acid, glycolic acid, m-hydroxybenzoic acid, p-hydroxybenzoic acid, 6-hydroxy-2-naphthalenecarboxylic acid and p-β-hydroxyethoxybenzoic acid. Preferred examples of the monofunctional component include alkoxycarboxylic acid, stearyl alcohol, benzyl alcohol, stearic acid, benzoic acid, t-butylbenzoic acid and benzoylbenzoic acid. Preferred examples of the trifunctional or higher polyfunctional component include tricarballylic acid, trimellitic acid, trimesic acid, pyromellitic acid, gallic acid, trimethylolethane, trimethylolpropane, glycerol, and pentaerythritol.

  As the polyester resin, a polybutylene terephthalate resin (hereinafter sometimes abbreviated as “PBT resin”) is more preferable, and terephthalic acid is the only dicarboxylic acid unit and 1,4-butanediol is the only diol unit. A polybutylene terephthalate homopolymer is preferred from the viewpoints of moldability and heat resistance. In the present invention, the PBT resin means that terephthalic acid accounts for 50 mol% or more of all dicarboxylic acid components, and 1,4-butanediol accounts for 50 mol% or more of all diols. The PBT resin further preferably has a terephthalic acid ratio in the dicarboxylic acid unit of 70 mol% or more, more preferably 90 mol% or more. Moreover, 70 mol% or more is preferable and the ratio of 1, 4- butanediol in a diol unit has more preferable 90 mol% or more. Use of such a PBT resin is preferred because mechanical characteristics and heat resistance tend to be further improved.

  The intrinsic viscosity of the PBT resin in the present invention is 0.5 to 3.0 dl / g as measured at 30 ° C. in a mixed solvent of 1,1,2,2-tetrachloroethane and phenol (1: 1 (weight ratio)). Preferably, 0.5 to 1.5 dl / g is more preferable, and 0.6 to 1.3 dl / g is more preferable. When the intrinsic viscosity is 0.5 dl / g or more, the mechanical properties are more effectively exhibited, and when the intrinsic viscosity is 3.0 dl / g or less, the molding process becomes easier. Further, two or more kinds of intrinsic viscosity PBT resins may be used in combination to be within the intrinsic viscosity range.

  When manufacturing a polyester resin, a well-known method is employable widely. For example, in the case of a PBT resin composed of a terephthalic acid component and a 1,4-butanediol component, either a direct polymerization method or a transesterification method can be employed. The direct polymerization method is, for example, a method in which terephthalic acid and 1,4-butanediol are directly esterified, and water is generated in the initial esterification reaction. The transesterification method is a method using, for example, dimethyl terephthalate as a main raw material, and alcohol is generated by an initial transesterification reaction. The direct esterification reaction is preferable from the viewpoint of raw material costs.

  In the present invention, when a polybutylene terephthalate resin is used, a polyester resin having a terminal carboxyl group concentration of preferably 40 eq / ton or less, more preferably 30 eq / ton or less is used. The terminal carboxyl group concentration in the present invention is a value obtained by dissolving 0.5 g of polybutylene terephthalate resin in 25 ml of benzyl alcohol and titrating using a 0.01 mol / l benzyl alcohol solution of sodium hydroxide, It is a carboxyl group equivalent per 106 g. As a method for adjusting the terminal carboxyl group concentration, for example, a raw material charging ratio at the time of polymerization, a polymerization catalyst species and amount, a polymerization temperature, a method of adjusting polymerization conditions such as a pressure reduction method, a method of reacting a terminal blocking agent, etc. Although any method can be applied, in the present invention, as described later, it is preferable to employ a method of adjusting the polymerization conditions. For example, terephthalic acid and 1,4-butanediol are melt polycondensed to produce a polybutylene terephthalate resin having a relatively low molecular weight, for example, an intrinsic viscosity of 0.1 to 0.9 g / g, and then the desired molecular weight is obtained. Can be obtained by solid-phase polycondensation. A lower terminal carboxyl group concentration is preferable from the viewpoint of hydrolysis resistance.

  As the polymerization method, it is preferable to use a direct polymerization method using a dicarboxylic acid as a main raw material, a continuous method in which an esterification reaction and a polycondensation reaction are continuously performed. The feed ratio of terephthalic acid as a raw material to 1,4-butanediol is preferably in the range of 1.1 to 5.0 moles of 1,4-butanediol with respect to 1 mole of terephthalic acid. More preferably, it is in the range of ˜4.5 mol.

  As the polymerization catalyst, various known catalysts can be used. Among them, it is preferable to use (i) a titanium compound and (ii) a group 1 metal compound and / or a group 2 metal compound. Since these polymerization catalysts are superior in dispersibility in the raw material mixture at the time of polymerization compared to other catalysts, the polymerization of the PBT resin can be promoted more effectively.

The use time of these polymerization catalysts is arbitrary, and examples of the use time include the following methods (1) to (4). Hereinafter, (i) a titanium compound is referred to as a “titanium catalyst”, (ii) a group 1 metal compound of a group 1 metal compound and / or a group 2 metal compound, a group 2 metal compound, respectively, a “group 1 metal catalyst”, Sometimes referred to as “Group 2 metal catalyst”.
(1) A method of using both the components (i) and (ii) in the esterification reaction (or transesterification reaction) and bringing them into a polycondensation reaction.
(2) A method of using both the components (i) and (ii) during the esterification reaction (or transesterification reaction) and using the remaining two components at the start of the polycondensation reaction or during the polycondensation reaction.
(3) A method of using one of the components (i) and (ii) at the time of esterification (or transesterification) and using the other at the start of the polycondensation reaction or during the polycondensation reaction.
(4) A method in which neither of the components (i) and (ii) is used during the esterification reaction (or transesterification reaction), and both components are used at the start of the polycondensation reaction.

  (I) There is no restriction | limiting in particular as titanium compound used for this invention, For example, titanium, such as inorganic titanium compounds, such as a titanium oxide and titanium tetrachloride, tetramethyl titanate, tetraisopropyl titanate, tetrabutyl titanate, etc. Examples include alcoholates and titanium phenolates such as tetraphenyl titanate. Of these, titanium alcoholates are preferable, tetraalkyl titanates are more preferable, and tetrabutyl titanate is particularly preferable.

  (Ii) The Group 1 metal compound and / or the Group 2 metal compound used in the present invention is not particularly limited. Specifically, for example, the Group 1 metal compound may be hydroxylated with lithium, sodium, potassium, rubidium, or cesium. Examples include various compounds such as substances, oxides, alcoholates, organic acid salts (acetates, phosphates, carbonates, etc.), which may be used alone or in combination of two or more. Good. Examples of Group 2 metal compounds include various compounds such as beryllium, magnesium, calcium, strontium, barium hydroxides, oxides, alcoholates, and organic acid salts (acetates, phosphates, carbonates, etc.). These may be used alone or in combination of two or more.

  Among them, from the viewpoints of handling and availability, and a catalytic effect, compounds such as lithium, sodium, potassium, magnesium, and calcium are preferable, and a lithium or magnesium compound that is excellent in catalytic effect and color tone is preferable, particularly a magnesium compound. Is preferred. Specific examples of the magnesium compound include magnesium acetate, magnesium hydroxide, magnesium carbonate, magnesium oxide, magnesium alkoxide, magnesium hydrogen phosphate, and the like. Of these, organic acid salts are preferable, and magnesium acetate is particularly preferable.

  In the PBT resin in the present invention, when (i) a titanium compound remains, the remaining amount is preferably small. (I) The titanium compound is preferably 80 ppm or less in terms of titanium atom, 70 ppm or less, particularly 60 ppm or less, more preferably 50 ppm or less, and particularly preferably 40 ppm or less. If the residual amount of the titanium compound is too large, the color tone, hydrolysis resistance and heat shock resistance of the PBT resin may decrease, or solution haze and foreign matter may increase. As a method for producing a PBT resin having such a residual amount of titanium compound, for example, terephthalic acid and 1,4-butanediol, and tetrabutyl titanate as a catalyst are used as titanium atoms with respect to the theoretical yield of polybutylene terephthalate. An amount of 80 ppm or less is added, and an ester exchange reaction is performed at a temperature in the range of 180 to 240 ° C. under normal pressure to obtain an oligomer, which can be obtained by proceeding polycondensation at 230 to 270 ° C. under reduced pressure.

  In the PBT resin in the present invention, when (ii) a group 1 metal compound and / or a group 2 metal compound remain, the amount thereof is preferably small. (Ii) The Group 1 metal compound and / or the Group 2 metal compound is preferably 50 ppm or less in terms of each metal atom, 40 ppm or less, particularly 30 ppm or less, more preferably 20 ppm or less, and particularly preferably 15 ppm or less. preferable. When there is too much residual amount of this group 1 metal compound and / or group 2 metal compound, the moldability of the PBT resin composition of this invention and the hydrolysis resistance of the resin molded product obtained may fall.

  The metal content such as titanium atom can be measured using a method such as atomic emission, atomic absorption, Inductively Coupled Plasma (ICP) after recovering the metal in the polymer by a method such as wet ashing.

  Examples of the polymerization catalyst for the PBT resin used in the present invention include (i) titanium compounds and (ii) Group 1 metal compounds and / or Group 2 metal compounds as described above. Tin or a tin compound may be used. Tin is usually used as a tin compound. Specifically, for example, dibutyltin oxide, methylphenyltin oxide, tetraethyltin oxide, hexaethylditin oxide, cyclohexahexylditin oxide, didodecyltin oxide, triethyltin hydrous oxide Oxide, triphenyltin hydroxide, triisobutyltin acetate, dibutyltin diacetate, diphenyltin dilaurate, monobutyltin trichloride, tributyltin chloride, dibutyltin sulfide, butylhydroxytin oxide, methylstannic acid, ethylstannic acid, butylstannic acid Etc.

  Since the tin or tin compound may deteriorate the color tone of the PBT resin, the residual amount of tin or tin compound in the PBT resin used in the present invention is preferably low, and more preferably does not remain. Specifically, the residual amount of tin compound is usually 200 ppm or less, preferably 100 ppm or less, and more preferably 10 ppm or less in terms of tin atoms.

  Further, in the production of the PBT resin in the present invention, in addition to the above-mentioned titanium catalyst, Group 1 metal catalyst, Group 2 metal catalyst, antimony compounds such as antimony trioxide, germanium compounds such as germanium dioxide and germanium tetroxide, Reaction assistants such as manganese compounds, zinc compounds, zirconium compounds, cobalt compounds, orthophosphoric acid, phosphorous acid, hypophosphorous acid, polyphosphoric acid, etc., and phosphorus compounds such as these ester compounds and metal salts may be used.

  As a specific example of the method for producing a PBT resin in the present invention, for example, in the case of a continuous esterification method using a direct polymerization method, the following method may be used. A dicarboxylic acid component mainly composed of terephthalic acid, which is a raw material, and a diol component mainly composed of 1,4-butanediol are mixed in a raw material mixing tank to form a slurry, and inside one or a plurality of esterification reaction tanks In the presence of a titanium catalyst and a Group 1 metal catalyst and / or a Group 2 metal catalyst, the temperature condition is usually 180 to 260 ° C, preferably 200 to 245 ° C, more preferably 210 to 235 ° C. The pressure (indicating absolute pressure; hereinafter the same) conditions are usually 10 to 133 kPa, preferably 13 to 101 kPa, more preferably 60 to 90 kPa, and usually 0.5 to 10 hours. Preferably, the esterification reaction is continuously performed for 1 to 6 hours.

  Any conventionally known esterification reaction vessel or transesterification reaction vessel can be used. Specifically, for example, a vertical stirring complete mixing tank, a vertical heat convection mixing tank, a tower type continuous reaction tank, and the like can be mentioned. These may be used as a single tank or as a plurality of reaction tanks in which the same or different reaction tanks are connected in series or in parallel. Among them, it is preferable to use a reaction tank having a stirring device. As the stirring device, in addition to a normal stirring device including a power unit, a bearing, a shaft, a stirring blade, etc., a turbine stator type high-speed rotary stirrer, a disc mill type stirrer Alternatively, a rotor mill type stirrer or the like capable of high speed rotation may be used.

  Next, the oligomer as the obtained esterification reaction product (or transesterification reaction product) is transferred to a polycondensation reaction tank. Although the esterification rate of this oligomer is arbitrary, it is usually 90% or more, preferably 95% or more, and the number average molecular weight is usually 300 to 3000, preferably 500 to 1500.

  The form of the polycondensation reaction tank is arbitrary, and examples thereof include a vertical stirring complete mixing tank, a vertical heat convection mixing tank, a tower-type continuous reaction tank, and the like, and these may be used in combination. Among these, at least one polycondensation reaction tank preferably has a stirrer, and the stirrer can be the same as the esterification reaction layer described above.

  The form of stirring is not particularly limited, and in addition to the usual stirring method in which the reaction solution in the reaction tank is directly stirred from the top, bottom, side, etc. of the reaction tank, a part of the reaction solution is connected to the reactor by piping or the like. A method of circulating the reaction liquid by taking it outside and stirring it with a line mixer or the like may be used, or a horizontal reactor having a rotation axis in the horizontal direction and excellent in self-cleaning may be used. Good.

  The polycondensation reaction is preferably performed in the presence of a titanium catalyst and a Group 1 metal catalyst and / or a Group 2 metal catalyst. The reaction temperature is usually 210 to 280 ° C, preferably 220 to 250 ° C, particularly preferably 230 to 245 ° C. For example, when using several reaction tanks, it is preferable that the temperature of the at least 1 reaction tank is 230-240 degreeC. The reaction is preferably performed under stirring conditions. The polycondensation reaction time is usually 1 to 12 hours, preferably 3 to 10 hours. The pressure condition of the reaction atmosphere is usually 27 kPa or less, preferably 20 kPa or less, and particularly preferably 13 kPa or less. For example, when a plurality of reaction vessels are used, the pressure in at least one of the reaction vessels is usually 1.3 kPa or less, particularly 0.5 kPa or less, particularly 0.3 kPa in order to suppress coloring and deterioration of the product. The following high vacuum is preferable.

  The polymer obtained by the polycondensation reaction is usually transferred from the bottom of the polycondensation reaction tank to a polymer extraction die and extracted in the form of a strand, and while being cooled with water or after being cooled with water, it is cut with a cutter to form pellets and chips. And so on.

  Further, the polycondensation reaction step of the PBT resin once produced a PBT resin having a relatively small molecular weight, for example, an intrinsic viscosity of about 0.1 to 0.9 dl / g by melt polycondensation, Solid phase polycondensation (solid phase polymerization) may be performed at a temperature below the melting point.

(Polyamide resin)
The polyamide resin in the present invention is a polyamide polymer having an acid amide group (—CONH—) in the molecule and capable of being melted by heating. Especially, the polyamide resin in which at least 1 type of monomer which comprises at least 1 type of a polyamide resin has an aromatic ring is preferable. Such a polyamide resin is preferable because the polyamide resin has a low water absorption rate, so that physical properties at the time of water absorption can be maintained, and foaming due to moisture at the time of welding can be further suppressed. The polyamide resin is preferably a polyamide resin containing, as a structural unit (a), at least one selected from a salt composed of an aliphatic diamine and an aromatic dicarboxylic acid and a salt composed of an aromatic diamine and an aliphatic dicarboxylic acid. . The proportion of the structural unit (a) in all structural units of the polyamide resin is preferably 30 mol% or more, more preferably 40 mol% or more.

  Specific examples of the polyamide resin in the present invention include various polyamide resins such as a lactam polycondensate, a polycondensate of diamine and dicarboxylic acid, and a polycondensate of ω-aminocarboxylic acid, or copolymers thereof. Polyamide resins and blends.

Examples of the lactam that is a raw material for polycondensation of polyamide resin include ε-caprolactam and ω-laurolactam.
Examples of the diamine include tetramethylene diamine, pentamethylene diamine, hexamethylene diamine, octamethylene diamine, undecamethylene diamine, dodecamethylene diamine, 2-methylpentamethylene diamine, (2, 2, 4- or 2, 4, 4-) Trimethylhexamethylenediamine, 5-methylnonanemethylenediamine, metaxylylenediamine (MXDA), paraxylylenediamine, 1,3-bis (aminomethyl) cyclohexane, 1,4-bis (aminomethyl) cyclohexane, 1-amino-3-aminomethyl-3,5,5-trimethylcyclohexane, bis (4-aminocyclohexyl) methane, bis (3-methyl-4-aminocyclohexyl) methane, 2,2-bis (4-aminocyclohexyl) ) Propane, bi (Aminopropyl) piperazine, aliphatic, such as aminoethylpiperazine, alicyclic, and a diamine of the aromatic and the like.
Examples of the dicarboxylic acid include adipic acid, suberic acid, azelaic acid, sebacic acid, dodecanedioic acid, terephthalic acid, isophthalic acid, 2-chloroterephthalic acid, 2-methylterephthalic acid, 5-methylisophthalic acid, and 5-sodium. Aliphatic, alicyclic, and aromatic dicarboxylic acids such as sulfoisophthalic acid, hexahydroterephthalic acid, and hexahydroisophthalic acid.
Examples of the ω-aminocarboxylic acid include 6-aminocaproic acid, 11-aminoundecanoic acid, 12-aminododecanoic acid, paraaminomethylbenzoic acid, and the like.

  As a raw material of the polyamide resin in the present invention, a compound having 4 to 15 carbon atoms is preferable. By setting the number of carbon atoms to 4 or more, it tends to be possible to suppress the hygroscopicity of the resulting polyamide resin from becoming too high, and by setting the number of carbon atoms to 15 or less, the rigidity can be further increased. More specifically, ε-caprolactam as the lactam, hexamethylenediamine and xylylenediamine as the diamine, and adipic acid, terephthalic acid and isophthalic acid as the dicarboxylic acid are easily available and advantageous in price. It is more preferable.

  The salt which is a structural unit of the polyamide resin can be obtained by neutralizing the above diamine and dicarboxylic acid in an aqueous solution at high temperature under pressure. The salt thus obtained, the above lactam, and ω-aminocarboxylic acid are condensed under pressure and high temperature to advance the oligomerization reaction, and then the polymerization proceeds under reduced pressure, which is used in the present invention. A polyamide resin can be produced.

  More preferably, the polyamide resin in the present invention includes a semi-aromatic polyamide resin and a blend of a semi-aromatic polyamide resin and an aliphatic polyamide resin as shown below. When blending and using a semi-aromatic polyamide resin and an aliphatic polyamide resin, the semi-aromatic polyamide resin and the aliphatic polyamide resin are preferably semi-aromatic polyamide resin / aliphatic polyamide resin = 95 / 5-20. / 80, more preferably in a weight ratio of 90/10 to 30/70.

  The semi-aromatic polyamide resin is a polyamide resin containing as a structural unit (a) at least one selected from a salt composed of an aliphatic diamine and an aromatic dicarboxylic acid and a salt composed of an aromatic diamine and an aliphatic dicarboxylic acid. Yes, preferably at least selected from homopolymers and copolymers consisting only of the structural unit (a) or polyamide structural units (a), and salts consisting of lactams, aliphatic diamines and aliphatic dicarboxylic acids. It is a polyamide copolymer comprising one type of structural unit (b). When both the structural units (a) and (b) are included, the molar ratio of the structural units (a) and (b) is preferably (a) / (b) = 98/2 to 30/70. A more preferable molar ratio is (a) / (b) = 95/5 to 35/65, and more preferably 90/10 to 40/60. By using such a polyamide structural unit, it is possible to more effectively suppress the water absorption rate of the polyamide resin from becoming too high, and to maintain good physical properties and dimensional accuracy at the time of water absorption, due to moisture at the time of laser welding. There is a tendency that defects such as foaming can be suppressed.

  Specific examples of such a preferred semi-aromatic polyamide resin include, for example, polyamide MXD6 mainly composed of a salt of metaxylylenediamine and adipic acid, metaxylylenediamine, paraxylylenediamine, and adipic acid as the main raw materials. Polyamide MP6, polyamide 6I mainly composed of hexamethylene diamine and isophthalic acid salt, salt of hexamethylene diamine and adipic acid / copolymer of salt of hexamethylene diamine and isophthalic acid (polyamide 66 / 6I) , A salt of hexamethylenediamine and isophthalic acid / a copolymer of a salt of hexamethylenediamine and terephthalic acid (polyamide 6I / 6T) and the like, and more preferably, polyamide MXD6, polyamide MP6 and polyamide 6I / 6T. is there.

  The semi-aromatic polyamide resin preferably has a specific apparent melt viscosity. A preferable apparent melt viscosity is a value measured from 750 to 8000 using a capillary rheometer (Capillograph 1C manufactured by Toyo Seiki Co., Ltd.), L / D of capillary is 30 mm / 1 mm, temperature is 280 ° C. and shear rate is 100 sec-1. Poise, more preferably 800 to 7500 poise, and still more preferably 850 to 7000 poise. By making the apparent melt viscosity 750 poise or more, the mechanical strength tends to be more excellent, and by setting it to 8000 poise or less, it is possible to prevent a decrease in fluidity and moldability.

Examples of the aliphatic polyamide resin include polyamide 4, polyamide 6, polyamide 11, polyamide 12, polyamide 46, polyamide 56, polyamide 66, polyamide 610, polyamide 612, and the like (polyamide 6/66 co-polymer). And a polyamide 6/12 copolymer).
The aliphatic polyamide resin preferably has a viscosity number of 70 to 200 ml / g measured at a temperature of 25 ° C. and 96 wt% sulfuric acid at a polyamide resin concentration of 0.5 wt% in accordance with the ISO 307 standard. By setting the viscosity number to 70 ml / g or more, the toughness and the appearance of the molded product can be made excellent. By setting the viscosity number to 200 ml / g or less, the compound and the molding process are facilitated, and a good appearance of the molded product is obtained. This is preferable.

  The terminal of the polyamide resin in the present invention may be sealed with a carboxylic acid or an amine, and is particularly preferably sealed with a carboxylic acid or amine having 6 to 22 carbon atoms. Specifically, examples of the carboxylic acid used for sealing include aliphatic monocarboxylic acids such as caproic acid, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, and behenic acid. Examples of the amine include aliphatic primary amines such as hexylamine, octylamine, decylamine, laurylamine, myristylamine, palmitylamine, stearylamine, and behenylamine. The amount of carboxylic acid or amine used for sealing is preferably about 30 μeq / g in consideration of the melt viscosity at the time of molding.

(Polyacetal resin)
The polyacetal resin in the present invention is a polymer produced by polymerization of formaldehyde or trioxane, and examples thereof include a homopolymer having an oxymethylene group as a repeating unit. In order to increase heat resistance and chemical resistance, it is common practice to convert terminal groups to ester groups or ether groups.
The polyacetal resin may be a block copolymer. This type of copolymer is composed of a homopolymer block having the above oxymethylene group as a repeating unit and another type of polymer block. Specific examples of other types of polymer blocks include, for example, polyalkylene glycol, polythiol, vinyl acetate, acrylic acid copolymer, hydrogenated butadiene, acrylonitrile copolymer, and the like.
The polyacetal resin may be a random copolymer. In this type of copolymer, formaldehyde and trioxane are copolymerized with other aldehydes, cyclic ethers, vinyl compounds, ketene, cyclic carbonates, epoxides, isocyanates, ethers, and the like. Specific examples of the compound to be copolymerized include ethylene oxide, 1,3-dioxolane, 1,3-dioxane, 1,3-dioxepene, epichlorohydrin, propylene oxide, isobutylene oxide and styrene oxide. In this type of copolymer, the polymerization catalyst is generally deactivated and the terminal is stabilized after cationic polymerization. A copolymer containing an oxymethylene group as a main repeating unit and containing an oxyalkylene group having 2 or more carbon atoms is widely used.

(Polyolefin resin)
The polyolefin resin in the present invention is mainly composed of an α-olefin homopolymer, a copolymer of -olefins α-olefin (multiple types may be used), and other unsaturated monomers (multiple types may be used). And the like. Here, the copolymer may be any type of copolymer such as block, random, graft, or a composite thereof. In addition, these olefin polymers are modified by chlorination, sulfonation, carbonylation and the like.
Examples of the α-olefin include ethylene, propylene, butene-1, pentene-1, hexene-1, heptene-1, octene-1, and the like. Among these, an α-olefin having 2 to 8 carbon atoms is preferable because of easy availability.
Examples of the unsaturated monomer include unsaturated organic compounds such as acrylic acid, methacrylic acid (hereinafter abbreviated as “(meth) acrylic acid”), (meth) acrylic acid ester, maleic acid, and the like. Examples thereof include acids, derivatives thereof (esters, anhydrides, etc.), unsaturated aliphatic cyclic olefins, and the like.
Specific examples of polyolefin resins include low density polyethylene, medium density polyethylene, high density polyethylene, polypropylene, polybutene, poly-4-methylpentene-1, propylene-ethylene block or random copolymer, and other copolymers with ethylene. And copolymers with various monomers.

(Polycarbonate resin)
As the polycarbonate resin in the present invention, either an aromatic polycarbonate resin or an aliphatic polycarbonate resin can be used, but an aromatic polycarbonate resin is preferred.
An aromatic polycarbonate resin is a thermoplastic polymer obtained by reacting an aromatic dihydroxy compound or a small amount of a polyhydroxy compound with phosgene or a carbonic acid diester. The aromatic polycarbonate resin may be branched or a copolymer. The production method of the aromatic polycarbonate resin is not particularly limited, and can be produced by a conventionally known phosgene method (interfacial polymerization method) or a melting method (transesterification method). Moreover, when using the aromatic polycarbonate resin obtained by a melting method, you may adjust and use the amount of OH groups of a terminal group.

  Examples of the aromatic dihydroxy compound used as a raw material for the aromatic polycarbonate resin include 2,2-bis (4-hydroxyphenyl) propane (that is, bisphenol A), tetramethylbisphenol A, and bis (4-hydroxyphenyl) -p-diisopropyl. Examples thereof include benzene, hydroquinone, resorcinol, 4,4-dihydroxydiphenyl, and bisphenol A is preferable. In addition, a compound in which one or more tetraalkylphosphonium sulfonates are bonded to the above aromatic dihydroxy compound can also be used.

  In order to obtain a branched aromatic polycarbonate resin, a part of the above-mentioned aromatic dihydroxy compound is mixed with a branching agent such as phloroglucin, 4,6-dimethyl-2,4,6-tri (4-hydroxyphenyl) heptene- 2,4,6-dimethyl-2,4,6-tri (4-hydroxyphenyl) heptane, 2,6-dimethyl-2,4,6-tri (4-hydroxyphenyl) heptene-3, 1,3 Polyhydroxy compounds such as 5-tri (4-hydroxyphenyl) benzene and 1,1,1-tri (4-hydroxyphenyl) ethane, and 3,3-bis (4-hydroxyaryl) oxindole (ie, isatin) Bisphenol), 5-chloroisatin, 5,7-dichloroisatin, 5-bromoisatin and the like may be substituted. The amount of the compound to be substituted is usually 0.01 to 10 mol%, preferably 0.1 to 2 mol%, based on the aromatic dihydroxy compound.

  As the aromatic polycarbonate resin, among the above-mentioned, polycarbonate resin derived from 2,2-bis (4-hydroxyphenyl) propane, or 2,2-bis (4-hydroxyphenyl) propane and other aromatic dihydroxy Polycarbonate copolymers derived from the compounds are preferred. Further, it may be a copolymer mainly composed of a polycarbonate resin, such as a copolymer with a polymer or oligomer having a siloxane structure. Furthermore, you may mix and use 2 or more types of the aromatic polycarbonate resin mentioned above.

  The molecular weight of the aromatic polycarbonate resin is preferably 13,000 to 30,000, preferably 16,000 to 28,000 as a viscosity average molecular weight converted from the solution viscosity measured at a temperature of 25 ° C. using methylene chloride as a solvent. More preferably, 17,000 to 24,000 is even more preferable. By setting the viscosity average molecular weight to 30,000 or less, the fluidity is kept good, and by setting the viscosity average molecular weight to 13,000 or more, the impact strength can be further improved.

(Polyphenylene ether resin)
The polyphenylene ether resin in the present invention is a homopolymer or copolymer having a phenylene ether structure represented by the following general formula (1).

一般式（１）中、２つのＲ^１は、それぞれ独立して、水素原子、ハロゲン原子、第１級若しくは第２級アルキル基、アリール基、アミノアルキル基、炭化水素オキシ基又はハロ炭化水素オキシ基を表し、２つのＲ^２は、それぞれ独立して、水素原子、ハロゲン原子、第１級若しくは第２級アルキル基、アリール基、ハロアルキル基、炭化水素オキシ基又はハロ炭化水素オキシ基を表し、ｎは１０以上の整数を表す。ただし、２つのＲ^１が共に水素原子になることはない。

In the general formula (1), two R ^{1 s} independently represent a hydrogen atom, a halogen atom, a primary or secondary alkyl group, an aryl group, an aminoalkyl group, a hydrocarbonoxy group, or a halohydrocarbonoxy. Each of the two R ^{2 s} independently represents a hydrogen atom, a halogen atom, a primary or secondary alkyl group, an aryl group, a haloalkyl group, a hydrocarbonoxy group, or a halohydrocarbonoxy group, n represents an integer of 10 or more. However, the two R ^{1 s} do not become hydrogen atoms.

R ¹ and R ² are preferably a hydrogen atom, a primary or secondary alkyl group, or an aryl group. Preferable examples of the primary alkyl group include, for example, methyl group, ethyl group, n-propyl group, n-butyl group, n-amyl group, isoamyl group, 2-methylbutyl group, n-hexyl group, 2, A 3-dimethylbutyl group, a 2,3- or 4-methylpentyl group, a heptyl group, etc. are mentioned. Preferable examples of the secondary alkyl group include isopropyl group, sec-butyl group, 1-ethylpropyl group and the like. Preferable examples of the aryl group include a phenyl group and a naphthyl group. In particular, R ¹ is more preferably a primary or secondary alkyl group having 1 to 4 carbon atoms or a phenyl group. R ² is more preferably a hydrogen atom.

Suitable polyphenylene ether homopolymers include, for example, poly (2,6-dimethyl-1,4-phenylene) ether, poly (2,6-diethyl-1,4-phenylene) ether, poly (2,6 2, such as -dipropyl-1,4-phenylene) ether, poly (2-methyl-6-ethyl-1,4-phenylene) ether, poly (2-methyl-6-propyl-1,4-phenylene) ether Examples thereof include polymers of 6-dialkylphenylene ether. Examples of the copolymer include various 2,6-dialkylphenol / 2,3,6-trialkylphenol copolymers.
As the polyphenylene ether resin of the present invention, poly (2,6-dimethyl-1,4-phenylene) ether and 2,6-dimethylphenol / 2,3,6-trimethylphenol copolymer are particularly preferable. Also suitable are polyphenylene ether resins containing molecular constituents that improve properties such as molecular weight, melt viscosity and impact strength.

  The intrinsic viscosity of the polyphenylene ether resin is preferably 0.2 to 0.8 dl / g, more preferably 0.2 to 0.7 dl / g as a value measured at 30 ° C. in chloroform. More preferably, it is 25-0.6 dl / g. By setting the intrinsic viscosity to 0.2 dl / g or more, it is possible to prevent a decrease in mechanical strength such as impact resistance of the resin composition, and by setting the intrinsic viscosity to 0.8 dl / g or less, the resin fluidity is further improved. It becomes good and the molding process becomes easy.

(Aromatic vinyl compound weight body)
The aromatic vinyl compound polymer is a polymer derived from a monomer compound having a structure represented by the following general formula (2).

一般式（２）中、Ｒ^３は、水素原子、低級アルキル基又はハロゲン原子を表し、Ｒ^４は水素原子、低級アルキル基、塩素原子又はビニル基を表し、ｎは１〜５の整数を表す。

In general formula (2), R ³ represents a hydrogen atom, a lower alkyl group or a halogen atom, R ⁴ represents a hydrogen atom, a lower alkyl group, a chlorine atom or a vinyl group, and n represents an integer of 1 to 5. .

  Specific examples of the aromatic vinyl compound polymer include, for example, polystyrene, rubber-reinforced polystyrene, polyvinyl chloride, styrene-acrylonitrile copolymer, acrylonitrile-butadiene-styrene copolymer, styrene-maleic anhydride copolymer, styrene. -Maleimide copolymer etc. are mentioned.

  As the thermoplastic resin of the present invention, the above-mentioned polyamide resin and polyester resin are preferable from the viewpoint of excellent balance of laser transmittance, mechanical strength, oil resistance, chemical resistance, heat resistance, durability, and moldability. .

<Glass fiber (B)>
The glass fiber (B) in the present invention is a fiber glass blended in plastic mainly for the purpose of improving mechanical strength, and the cross section perpendicular to the length direction of the fiber is not circular as in the prior art. It is characterized by having a flat shape (hereinafter sometimes referred to as “flat glass fiber”). Examples of the flat shape of the flat glass fiber are illustrated as eyebrows, ovals, and ellipses in FIGS. 1A, 1B, and 1C of Patent Document 6, respectively. In FIG. 1, the short diameter is (D1), the long diameter is (D2), the degree of flatness of the glass fiber is the flatness, and it is expressed as long diameter (D2) / short diameter (D1). In the present invention, the aspect ratio is required to be 1.5 or more, preferably 1.5 to, more preferably 2.5 to 6, and 3 to 4.5. Is more preferable. By setting the flatness to 1.5 or more, the transmittance is improved, and the warpage and molding shrinkage of the molded product can be effectively improved.

As the cross-sectional shape of the glass fiber (B), for example, a saddle shape having a constricted central portion in the longitudinal direction as shown in FIG. 1 (a) of JP-A-62-2268612, (B) an ellipse that has a portion that is substantially parallel to the position of symmetry with respect to the center of gravity of the cross section, an ellipse, a rectangle, etc. Can be mentioned. However, if the cross section is bowl-shaped, the central part of the cross section is constricted, so the strength of that part may be low and the constricted part may crack, and the constriction of the constricted part with the resin may be inferior Therefore, the cross-sectional shape is preferably oval, elliptical, or rectangular. The glass fiber having such a cross-sectional shape is easier to orient the fibers along the flow direction of the resin at the time of molding than the glass fiber having a normal cross section, and the laser light is scattered and the transmittance is reduced. Can be suppressed. In particular, when the degree of flatness of the cross section is large, resin flow in the fiber cross-section major axis (D2) direction occurs in addition to resin flow in the fiber length direction, so that the glass fibers are oriented in parallel along the (D2) direction. It becomes easy. In particular, the orientation tendency is strong in the vicinity of the surface of the molded product. The laser transmittance is improved by the influence of the fiber orientation characteristic of such flat glass fibers, which does not normally occur in a circular cross section.
Moreover, since the influence of the orientation of the fibers along the major axis (D2) direction appears more remarkably when the cross section is oval, glass fibers having an oval cross section are preferable in the present invention. When the cross-sectional shape is a bowl shape or an ellipse, the flow of the resin in the major axis (D2) direction is hindered by the eyebrow-shaped groove or the oval weir, and a part of the flow flows in the fiber length direction. Due to the tendency, the glass fibers are hardly aligned along the (D2) direction, and the laser transmittance improving effect is slightly inferior to the oval glass fibers. Accordingly, an oval shape is more preferable as the cross-sectional shape.

  Moreover, although the thickness of a flat glass fiber (B) is arbitrary, it is preferable that a short diameter (D1) is 0.5-25 micrometers and a long diameter (D2) is 1.25-300 micrometers. By setting it as such thickness, it becomes easy to spin the glass fiber, the contact area with the resin is increased, and a sufficient reinforcing effect tends to be obtained. In the present invention, it is preferable that the minor axis (D1) is 3 μm or more and the flatness is 2.5 or more.

Further, the flat glass fiber (B) has a fiber length of 10 or more in terms of aspect ratio (glass fiber length (L) / ((D1 + D2) × 0.5)), rigidity, mechanical strength, fluidity. From the viewpoint of the above, it is preferably 15 to 100.
Note that the short diameter (D1) and long diameter (D2) for calculating the flatness ratio are the values if there is a nominal value by the manufacturer, but if there is no nominal value, the micrograph of the cross section of the glass fiber that is the raw material Can be obtained by measuring the actual size. Further, the glass fiber length (L) is set to a value if there is a nominal value by the manufacturer, but if there is no nominal value, it can be obtained by measuring the actual size from a micrograph. The short diameter (D1), the long diameter (D2) and the fiber length (L) are obtained by measuring the length of 2000 glass fibers with respect to the obtained photographic image using image analysis software. did.

As glass fiber (B), what consists of compositions, such as A glass, C glass, and E glass, is preferable, and especially E glass (non-alkali glass) is a point which does not have a bad influence on the thermal stability of a thermoplastic resin. preferable. A glass having a refractive index of 1.560 to 1.600 can also be used. The glass is usually composed of components such as MgO, TiO ₂ and ZnO except for B ₂ O ₃ and F ₂ components from the components constituting E glass (refractive index of 1.555) used for polyester resins and polyamide resins. By adopting the glass, the laser transmittance of the resin composition of the present invention can be further improved. In general, it is preferable to use a short fiber type (chopped strand) from the viewpoint of ease of handling and the like, but especially when impact resistance is required, Since it is necessary to keep the fiber length of the glass fiber longer, it is preferable to use the long fiber type.

  The glass fiber (B) of the present invention is preferably surface-treated with a sizing agent and / or a surface treatment agent, if necessary, from the viewpoint of handling and adhesion to the resin. Examples of the sizing agent and / or surface treatment agent include silane coupling agents such as γ-methacryloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, and γ-aminopropyltriethoxysilane. . Further, if necessary, a lubricant such as a fatty acid amide compound, silicone oil, an antistatic agent such as a quaternary ammonium salt, a resin having a film forming ability such as an epoxy resin or a urethane resin, and a resin having the film forming ability A mixture of a heat stabilizer and / or a flame retardant can also be used in combination. The adhesion amount of the sizing agent and / or surface treatment agent is preferably 0.01% by weight or more of the glass fiber weight. The glass fiber (B) may be used after being surface-treated or converged with these compounds in advance, or may be added simultaneously with the production of the resin composition pellets used in the resin molded product of the present invention.

  The glass fiber (B) of the present invention can be produced using a method described in, for example, Japanese Patent Publication No. 3-59019, Japanese Patent Publication No. 4-13300, Japanese Patent Publication No. 4-32775, and the like. For example, the bushing used for discharging the melt can be manufactured by spinning using a nozzle having an appropriate hole shape such as an oval shape, a saddle shape, an elliptical shape, or a rectangular slit shape. Also, a melt is spun from a plurality of nozzles provided in close proximity with various cross-sectional shapes (including a circular cross-section), and the spun melt filaments are joined together to form a single filament. Can be manufactured. When bundling or surface-treating glass fibers, bundling or surface treatment can be performed by immersing the glass fibers in the bundling agent or surface treatment agent using a bundling agent or surface treatment agent coating apparatus provided in the middle.

The compounding quantity of glass fiber (B) is 10-150 weight part with respect to 100 weight part of thermoplastic resins (A) containing at least 1 sort (s) of polyester resin or polyamide resin, Preferably it is 20-120 weight part. . If the blending amount of the glass fiber is less than 10 parts by weight, the reinforcing effect is small and the elastic modulus and impact resistance are insufficient, and if it exceeds 150 parts by weight, melt kneading becomes difficult and the transmittance of the laser beam is unfavorable. When 35 parts by weight or more of the glass fiber (B) is blended, the effect of adding the flat glass fiber is sufficiently exhibited, and the difference in effect from the circular cross-section glass fiber is clearer.
Moreover, in this invention, you may mix | blend a part of flat glass fiber (B) to mix | blend with the glass fiber (flat rate 1) of a general circular section. In that case, the flat glass fiber and the circular cross-section glass fiber having a higher flatness ratio, so that the weight average value of the flatness ratio of the circular cross-section glass fiber and the flat glass fiber is within the range of the flat ratio defined in the present invention, It is preferable to mix in consideration of each ratio.

<Colorant (C)>
You may mix | blend colorants, such as dye and a pigment, with the thermoplastic resin composition of this invention. It is preferable to select and mix the dyes and pigments so that the light transmittance at a wavelength of 960 nm of the molded product having a thickness of 2 mm is 10% or more. As the dye, an anthraquinone-based, indigoid-based, perylene-based, perinone-based, azo-based, methine-based, phthalocyanine-based, anthrapyridone-based oil-soluble dye or disperse dye can be preferably used. As the pigment, both inorganic pigments and organic pigments can be preferably used. Examples of inorganic pigments include oxides, sulfides, sulfates, and carbon black. Examples of organic pigments include azo, phthalocyanine, anthraquinone, perylene, perinone, quinacridone, and dioxazine.
The blending amount of the colorant (C) is preferably 0.005 to 5 parts by weight, more preferably 0.01 to 100 parts by weight with respect to 100 parts by weight of the thermoplastic resin (A) containing at least one polyester resin or polyamide resin. 1 part by weight. By making the blending amount of the colorant within the above range, the dispersibility in the thermoplastic resin composition can be improved, and bleeding out to the surface of the molded product and reduction in mechanical strength can be suppressed.

<Other additives>
You may mix | blend another additive with the resin composition of this invention in the range which does not deviate from the meaning of this invention. Examples of other additives include antioxidants, heat stabilizers, flame retardants, lubricants, mold release agents, catalyst deactivators, and crystal nucleating agents. These additives can be added during or after the polymerization of the respective thermoplastic resins (A) used. Furthermore, in order to impart desired performance to the thermoplastic resin (A), an impact resistance improver, an ultraviolet absorber, a weather resistance stabilizer, an antistatic agent, a foaming agent, a plasticizer, and the like may be blended.

  The antioxidant has the effect of more effectively improving the heat aging resistance of the thermoplastic resin composition of the present invention and further improving the retention such as color tone, tensile strength, and elongation. As this antioxidant, it is preferable to mix | blend 1 or more types of antioxidant chosen from a phenolic antioxidant, sulfur type antioxidant, and phosphorus antioxidant. The blending amount of the antioxidant is preferably 0.001 to 2 parts by weight, more preferably 100 parts by weight of the thermoplastic resin (A) including at least one polyester resin or polyamide resin. Is 0.03 to 1.5 parts by weight. By making the blending amount of the antioxidant 0.001 part by weight or more, the antioxidant effect is more satisfactorily exhibited, and by making it 2 parts by weight or less, it is easier to suppress the deterioration of oxidation heat stability. In addition to the tendency, it becomes possible to make the decomposition of the resin during melt-kneading less likely to occur.

  The phenolic antioxidant means an antioxidant having a phenolic hydroxyl group, and among them, a hindered phenolic antioxidant is preferably used. The hindered phenol antioxidant is an antioxidant in which one or two carbon atoms adjacent to a carbon atom of an aromatic ring to which a phenolic hydroxyl group is bonded are substituted with a substituent having 4 or more carbon atoms. Say. The substituent having 4 or more carbon atoms may be bonded to a carbon atom of the aromatic ring by a carbon-carbon bond, or may be bonded via an atom other than carbon.

  Non-hinders such as p-cyclohexylphenol, 3-tert-butyl-4-methoxyphenol, 4,4′-isopropylidenediphenol, 1,1-bis (4-hydroxyphenyl) cyclohexane as phenolic antioxidants Dophenol antioxidant, 2-tert-butyl-4-methoxyphenol, 2,6-di-tert-butyl-p-cresol, 2,4,6-tri-tert-butylphenol, 4-hydroxymethyl-2 , 6-di-tert-butylphenol, styrenated phenol, 2,5-di-tert-butylhydroquinone, octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, triethylene glycol bis [3- (3-tert-butyl-5-methyl-4 Hydroxyphenyl) propionate], 1,6-hexanediol bis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], pentaerythritol tetrakis [3- (3,5-di-tert- Butyl-4-hydroxyphenyl) propionate], 2,2′-methylenebis (4-methyl-6-tert-butylphenol), 2,2′-methylenebis (6-tert-butyl-4-ethylphenol), 2,2 '-Methylenebis [4-methyl-6- (1,3,5-trimethylhexyl) phenol], 4,4'-methylenebis (2,6-di-tert-butylphenol), 4,4'-butylidenebis (3- Methyl-6-tert-butylphenol), 2,6-bis (2-hydroxy-3-tert) Butyl-5-methylbenzyl) -4-methylphenol, 1,1,3-tris [2-methyl-4-hydroxy-5-tert-butylphenyl] butane, 1,3,5-trimethyl-2,4 6-tris [3,5-di-tert-butyl-4-hydroxybenzyl] benzene, tris (3,5-di-tert-butyl-4-hydroxybenzyl) isocyanurate, tris [3- (3,5- Di-tert-butyl-4-hydroxyphenyl) propionyloxyethyl] isocyanurate, 4,4′-thiobis (3-methyl-6-tert-butylphenol), 2,2′-thiobis (4-methyl-6-tert) -Butylphenol), 4,4'-thiobis (2-methyl-6-tert-butylphenol), thiobis (β-naphthol), N N'- hexamethylene bis (3,5-di -tert- butyl-4-hydroxy - such as hindered phenolic antioxidants such as hydrocinnamate raw bromide and the like. In particular, hindered phenol-based antioxidants can be suitably used as radical trapping agents because they tend to be stable radicals themselves. The molecular weight of the hindered phenol antioxidant is usually 200 or more, preferably 500 or more, and the upper limit is usually 3000.

The sulfur-based antioxidant in the present invention refers to an antioxidant having a sulfur atom. 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 isopropyl Examples include xanthate and trilauryl trithiophosphite. In particular, a thioether-based antioxidant having a thioether structure can be suitably used because it receives oxygen from an oxidized substance and reduces it.
The molecular weight of the sulfur-based antioxidant is usually 200 or more, preferably 500 or more, and the upper limit is usually 3000.

The phosphorus antioxidant in the present invention refers to an antioxidant having a phosphorus atom, and is an inorganic antioxidant compound such as sodium phosphite and sodium hypophosphite, or an organic antioxidant having a P (OR) 3 structure. It is preferable that it is an agent. Here, R is an alkyl group, an alkylene group, an aryl group, an arylene group, etc., and three Rs may be the same or different, and any two Rs are bonded to each other to form a ring structure. It may be. Examples of phosphorus antioxidants include triphenyl phosphite, diphenyl decyl phosphite, phenyl diisodecyl phosphite, tri (nonylphenyl) phosphite, bis (2,4-di-tert-butylphenyl) pentaerythritol diphos. Phyto, bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite and the like can be mentioned.
The blending amount of the phenol-based antioxidant, the sulfur-based antioxidant and the phosphorus-based antioxidant is preferably 0.001 with respect to 100 parts by weight of the thermoplastic resin (A) containing at least one polyester resin or polyamide resin. It is -1.5 weight part, More preferably, it is 0.03-1 weight part. By making the blending amount 0.001 part by weight or more, the antioxidant effect is more effectively exhibited, and by making the blending amount 1.5 part by weight or less, it tends to suppress the decrease in oxidation heat stability. In addition, it becomes possible to make the decomposition of the resin during the melt-kneading more difficult to occur.

  Moreover, a copper compound can be further added to the thermoplastic resin composition of the present invention as a heat stabilizer. When a polyamide resin is included as the thermoplastic resin, in particular, when a copper compound is added, the heat resistance of the resin composition is further improved, and a decrease in transmittance due to a deteriorated resin tends to be suppressed. Specific examples of copper compounds include cuprous chlorides such as cuprous chloride, cupric chloride, cuprous bromide, cupric bromide, cuprous iodide, cupric iodide, etc. And copper compounds of organic acids such as cupric sulfate, cupric nitrate, copper phosphate, cuprous acetate, cupric acetate, cupric salicylate, cupric stearate, cupric benzoate and the like Examples thereof include complex compounds of the copper halide compound with xylylenediamine, 2-mercaptobenzimidazole, benzimidazole, and the like. Among these, monovalent copper compounds are preferable, and cuprous acetate and cuprous iodide are more preferable.

  The compounding amount of the copper compound is not particularly limited, but is usually 0.01 to 2 parts by weight with respect to 100 parts by weight of the thermoplastic resin (A) containing at least one polyester resin or polyamide resin, preferably 0.015 to 1 part by weight. When the blending amount is 0.01 parts by weight or more, the thermal stability tends to be exhibited more easily, and when it is 2 parts by weight or less, it is more effective that the resin is colored and the mechanical properties are lowered. It is preferable because it tends to be suppressed. Two or more copper compounds may be used in combination.

  In the present invention, an alkali halide compound may be added. In particular, it is preferable to employ in combination with a copper compound. Examples of the alkali halide compound include, for example, lithium chloride, lithium bromide, lithium iodide, potassium chloride, potassium bromide, potassium iodide, sodium bromide and sodium iodide. You may use together. Among these, potassium iodide and sodium iodide are particularly preferable. When the copper compound and the alkali halide compound are used in combination, the amount of the copper compound is preferably 0.005 to 1 weight with respect to 100 parts by weight of the thermoplastic resin (A) containing at least one polyester resin or polyamide resin. Parts, more preferably 0.01 to 0.5 parts by weight, and the alkali halide compound is preferably 0.01 to 2 parts by weight, more preferably 0.05 to 1 part by weight. Moreover, 0.015-3 weight part is preferable with respect to 100 weight part of thermoplastic resins (A) containing at least 1 type of polyester resin or polyamide resin, and the total compounding quantity of both is 0.06-1.5 weight part. Is more preferable.

  Examples of the impact resistance improver in the present invention include thermoplastic elastomers such as olefins, styrenes, polyesters, polyamides, and urethanes, and core-shell polymers.

  Preferred as the olefin-based elastomer is a copolymer mainly composed of ethylene and / or propylene, specifically, an ethylene-propylene copolymer, an ethylene-butene copolymer, an ethylene-octene copolymer, an ethylene. -Propylene-butene copolymer, ethylene-propylene-diene copolymer, ethylene-ethyl acrylate copolymer, ethylene-vinyl acetate copolymer, ethylene-glycidyl methacrylate copolymer and the like. Among these, an ethylene-propylene copolymer and an ethylene-butene copolymer are more preferable from the viewpoint of easy modification in the case of acid modification and a large impact resistance improving effect.

  Examples of the styrene elastomer include a block copolymer composed of a polymer block mainly composed of a vinyl aromatic compound such as styrene and a polymer block mainly composed of an unhydrogenated and / or hydrogenated conjugated diene compound. . Examples of the vinyl aromatic compound constituting the block copolymer include styrene, α-methylstyrene, vinyltoluene, p-tertiary butylstyrene, divinylbenzene, p-methylstyrene, 1,1-diphenylstyrene, and the like. One or more types can be selected from among them, and styrene is preferable among them. Examples of the conjugated diene compound include butadiene, isoprene, 1,3-pentadiene, 2,3-dimethyl-1,3-butadiene, pyrylene, 3-butyl-1,3-octadiene, phenyl-1,3- One or more types can be selected from butadiene and the like, and butadiene, isoprene and combinations thereof are particularly preferable. The copolymerization ratio of the vinyl aromatic compound and the conjugated diene compound is preferably 5/95 to 70/30, and more preferably 10/90 to 60/40. Examples of such block copolymers include various a-b-a type triblocks such as styrene-ethylene-butylene-styrene copolymer (SEBS) and styrene-ethylene-propylene-styrene copolymer (SEPS). Structures are commercially available and are readily available.

  Polyester elastomers include aromatic polyesters such as polyethylene terephthalate and polybutylene terephthalate as hard segments, polyethers such as polyethylene glycol, polypropylene glycol, and polytetramethylene glycol, or polyethylene adipate, polybutylene adipate, and polycaprolactone. The block copolymer which uses the aliphatic polyester of this as a soft segment is mentioned. Although the polyester-type elastomer used by this invention is not limited to this, The polyester-type elastomer illustrated above is preferable from a compatible viewpoint.

  Examples of the polyamide-based elastomer include block copolymers having polyamide 6, polyamide 66, polyamide 11, polyamide 12 and the like as hard segments and polyether or aliphatic polyester as soft segments, but are not limited thereto. Absent. As the polyether and the aliphatic polyester, the same compounds as those used in the polyester elastomer can be used.

  As urethane-based elastomers, by reacting diisocyanates such as 4,4′-diphenylmethane diisocyanate, 4,4′-dicyclohexylmethane diisocyanate, tolylene diisocyanate, hexamethylene diisocyanate and glycols such as ethylene glycol and tetramethylene glycol. Although the block copolymer which makes the obtained polyurethane a hard segment and makes a polyether or aliphatic polyester a soft segment is mentioned, it is not limited to this. As the polyether and the aliphatic polyester, the same compounds as those used in the polyester elastomer can be used.

  The core-shell polymer is a core-shell type graft copolymer in which a rubber layer is included in a glassy resin. The particle size of the rubber layer of the core is preferably 1.0 μm or less, more preferably 0.2 to 0.6 μm. When the weight average particle diameter of the rubber layer is 1.0 μm or less, the impact resistance improving effect tends to be more easily exhibited. Examples of the rubber layer include silicon-based, diene-based, and acrylic elastomers, and two or more of these may be copolymerized.

From the viewpoint of mechanical strength, thermal stability and fluidity, the impact resistance improver is preferably 0.05 to 5% by weight, more preferably about 0.2 to 4% by weight in the polymer. Or an epoxy-modified one is preferred.
The blending amount of the impact modifier is preferably 0.5 to 40 parts by weight, more preferably 2 with respect to 100 parts by weight of the thermoplastic resin (A) containing at least one polyester resin or polyamide resin. It is -35 weight part, More preferably, it is 5-30 weight part. By making the blending amount 0.5 parts by weight or more, the impact resistance can be made more excellent, and by making it 40 parts by weight or less, heat resistance, ultraviolet aging resistance, and a decrease in transmittance can be achieved. Can be suppressed.

  The flame retardant is not particularly limited, and examples thereof include organic flame retardants such as organic halogen compounds, antimony compounds, phosphorus compounds, nitrogen compounds, and inorganic flame retardants. Examples of the organic halogen compound include brominated polycarbonate, brominated epoxy resin, brominated phenoxy resin, brominated polyphenylene ether resin, brominated polystyrene resin, brominated bisphenol A, pentabromobenzyl polyacrylate and the like. Examples of the antimony compound include antimony trioxide, antimony pentoxide, sodium antimonate, and the like. Examples of the phosphorus compound include phosphate esters, polyphosphoric acid, ammonium polyphosphate, red phosphorus, and phosphazene compounds such as phenoxyphosphazene and aminophosphazene having a bond of a phosphorus atom and a nitrogen atom in the main chain. Examples of the nitrogen-based compound include melamine, cyanuric acid, melamine cyanurate, and the like. Examples of the inorganic flame retardant include aluminum hydroxide, magnesium hydroxide, silicon compound, boron compound and the like.

  The blending amount of the flame retardant is preferably 0.1 to 80 parts by weight, more preferably 1 to 60 parts by weight with respect to 100 parts by weight of the thermoplastic resin (A) containing at least one polyester resin or polyamide resin. Preferably it is 1-50 weight part. When the blending amount is 0.1 parts by weight or more, flame retardancy can be more effectively expressed, and when it is 80 parts by weight or less, physical properties, particularly mechanical strength, can be kept higher. .

  The thermoplastic resin composition of the present invention can be blended with a thermosetting resin such as an epoxy resin, a phenol resin, a melamine resin, or a silicone resin within a range that does not impair the effects of the present invention. These thermosetting resins may be blended as a part of the thermoplastic resin (A) containing at least one polyester resin or polyamide resin, or two or more kinds may be used in combination. The blending amount of these resins is preferably 50% by weight or less, more preferably 45% by weight or less in the resin component.

  In the laser welding thermoplastic resin composition of the present invention, the light transmittance at a wavelength of 960 nm of a molded product having a thickness of 2 mm made of the resin composition is preferably 10% or more, and more preferably 15% or more. More preferred.

  Although the manufacturing method in particular of the thermoplastic resin composition of this invention is not restrict | limited, The method of using the uniaxial or biaxial extruder which has the equipment which can be devolatilized from a vent port as a kneading machine is preferable. The thermoplastic resin (A) containing at least one polyester resin or polyamide resin, glass fiber (B), and other additives blended as necessary may be supplied to the kneader in a lump. Then, other blending components may be sequentially supplied to the thermoplastic resin (A) component. The glass fiber (B) is preferably supplied from the middle of the extruder in order to prevent the glass fiber from being crushed during kneading. Moreover, you may mix and knead | mix beforehand 2 or more types of components chosen from each component. For example, when blending the colorant (C), a master pellet prepared by kneading a colorant (C) larger than a predetermined blending ratio in a part of the thermoplastic resin (A) is prepared in advance, and this is mixed with the remaining blending. The thermoplastic resin composition of the present invention can also be obtained by melt mixing and extrusion with the components to obtain a predetermined blending ratio.

  The method for producing a molded article using the thermoplastic resin composition of the present invention is not particularly limited, and molding methods generally used for thermoplastic resins, that is, injection molding, hollow molding, extrusion molding, press molding, etc. A molding method can be applied. In this case, a particularly preferable molding method is injection molding because of good fluidity. In the injection molding, the resin temperature is preferably controlled to 240 to 280 ° C.

  The thermoplastic resin composition of the present invention is suitable for a resin material for laser welding. In particular, at least one of the members using the thermoplastic resin composition of the present invention can be firmly bonded to each other, and can be preferably used for the production of a molded product having two or more resin members. The shape of the member is not particularly limited, but is usually a shape having at least a surface contact portion (a flat surface or a curved surface) because the members are joined and used by laser welding. In laser welding, laser light that has passed through a laser-transmitting member is absorbed by the laser-absorbing member, melted, and both members are welded. Since the thermoplastic resin composition of the present invention has a high permeability to laser light despite containing the reinforcing filler, it can be preferably used as a member through which the laser light is transmitted. Here, the thickness of the member through which the laser passes (thickness in the laser transmission direction in the portion through which the laser beam passes) can be determined as appropriate in consideration of the application, the composition of the composition, and the like. Yes, preferably 4 mm or less.

As a laser light source used for laser welding of the present invention, for example, a gas laser such as an Ar laser (510 nm), a He—Ne laser (630 nm), a CO ₂ laser (10600 nm), or a liquid laser such as a dye laser (400 to 700 nm). Solid-state lasers such as YAG laser (1064 nm), semiconductor lasers (655 to 980 nm), and the like can be used. A semiconductor laser is preferably used in terms of beam quality and cost. Further, the laser type can be appropriately selected depending on the type of the welding partner material.

More specifically, for example, when welding a member made of the thermoplastic resin composition (I) of the present invention and a member made of the resin composition (II) having laser absorption, first, the locations where the two are welded together Are in contact with each other. At this time, surface contact is desirable between the two welded portions, and may be flat surfaces, curved surfaces, or a combination of flat and curved surfaces. Next, laser light is irradiated from the member side made of the thermoplastic resin composition (I) of the present invention (preferably irradiated perpendicularly to the adhesive surface). At this time, the laser beam may be condensed at the interface between the two using a lens system if necessary. The condensed beam passes through the member made of the thermoplastic resin composition (I) of the present invention, is absorbed near the surface of the member made of the resin composition (II), generates heat, and melts. Next, the heat is transferred to the member made of the thermoplastic resin composition (I) of the present invention by heat conduction and melted to form a molten pool at the interface between the two, and after cooling, the two are joined.
The molded product in which the members are welded in this way has high bonding strength. In addition, the molded product in the present invention means a product in which at least two members are welded, and includes a member that forms a part of these in addition to a finished product or a part.

  The member made of the resin composition (II) is not particularly limited as long as it contains at least a resin and can be welded to the member made of the resin composition (I) of the present invention. The resin contained in the resin composition (II) may be the same type of resin as the resin composition (I) or a different type of resin, but has good compatibility with the resin composition (I). From these points, it is particularly preferable that the resin is the same type as the resin composition (I). Moreover, resin composition (II) may be comprised from 2 or more types of resin.

  The resin composition (II) preferably has an absorption wavelength within the range of the wavelength of the laser beam to be irradiated. Furthermore, you may express the absorption characteristic by making a resin composition (II) add and contain a light absorber, for example, a color pigment. Examples of the color pigment include inorganic pigments (black pigments such as carbon black (for example, acetylene black, lamp black, thermal black, furnace black, channel black, ketjen black), red pigments such as iron oxide red, molyb And orange pigments such as date orange, white pigments such as titanium oxide) and organic pigments (yellow pigment, orange pigment, red pigment, blue pigment, green pigment, etc.). Among these, inorganic pigments generally have a strong hiding power and can be preferably used for the resin composition (II) on the laser absorption side. These light absorbers may be used in combination of two or more. It is preferable that the compounding quantity of a light absorber is 0.01-1 weight part with respect to 100 weight part of resin components.

  The integrally molded product obtained in the present invention has good mechanical strength, high welding strength, and less resin damage due to laser light irradiation, so that it can be used in various applications such as various storage containers, electrical / electronic devices. It can be applied to parts, office automate (OA) equipment parts, home appliance parts, machine mechanism parts, vehicle mechanism parts, and the like. In particular, food containers, chemical containers, oil and fat product containers, vehicle hollow parts (various tanks, intake manifold parts, etc.), vehicle electrical parts (various control units, ignition coil parts, etc.) motor parts, various sensor parts, connectors It can be suitably used for parts, switch parts, breaker parts, relay parts, coil parts, transformer parts, lamp parts and the like.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to a following example at all unless the summary is exceeded.

[Various measurement methods]
(1) Light transmittance After drying each resin composition of Table 1 at 120 degreeC for 5 hours, it used Table 1 using the injection molding machine (Sumitomo Heavy Industries, Ltd. "model: SE-50D"). A test piece for measuring light transmittance (length 128 mm, width 13 mm, thickness 1.5 or 2 mm) was produced under the cylinder temperature and mold temperature conditions described in 1). The light transmittance is measured using a visible / ultraviolet spectrophotometer (“UV-3100PC” manufactured by Shimadzu Corporation), and the ratio of transmitted light intensity to incident light intensity in the near infrared region 960 nm is expressed as a percentage (%). did.

(2) Laser weldability As shown in FIG. 1, the test pieces were overlapped and irradiated with laser. In FIG. 1, (a) shows a view of the test piece from the side, and (b) shows a view of the test piece from above. 1 is a test piece (length 128 mm, width 13 mm, thickness 2 mm) produced under the same conditions as the light transmittance measurement test piece of (1) above, and 2 is a thermoplastic resin composition which is a mating material to be joined. A test piece (made in the same manner as the test piece 1) made of (II), 3 indicates a laser irradiation spot.
The test piece 1 was overlapped with the laser transmission side and the test piece 2 made of the resin composition (II) was overlapped with the laser absorption side, and the laser was irradiated from the transmission side. As the laser welding apparatus, a batch irradiation type “IRAM-300” manufactured by Nippon Emerson Co., Ltd. was used, the laser light wavelength was 960 nm, the welding spot was 3 mm × 13 mm, and the pressure was 4.8 MPa. The laser irradiation time was 17 sec when the resin component was a polyester resin and 10 sec when the resin component was a polyamide resin.
Laser welding strength measurement was performed using the welded test piece. The welding strength is measured by using a tensile tester (Instron “5544”), and welding and integrating the test pieces 1 and 2 with clamps at both ends in the major axis direction. Evaluation was performed by pulling at 5 mm / min. The laser welding strength is indicated by the tensile shear fracture strength of the welded portion.

(3) Tensile strength and Charpy impact strength Each resin composition shown in Table 1 was dried at 120 ° C. for 5 hours and then used with an injection molding machine (“Model: SG-75MIII” manufactured by Sumitomo Heavy Industries, Ltd.). ISO test pieces for tensile test and Charpy impact test were prepared under the cylinder temperature and mold temperature conditions shown in Table 1. With respect to the ISO test piece, the tensile strength was measured in accordance with the ISO 527 standard, and the notched Charpy impact strength was measured in accordance with the ISO 179 standard.

(4) Evaluation method of properties of polybutylene terephthalate resin Intrinsic viscosity (IV):
It calculated | required in the following way using the Ubbelohde type viscometer. That is, using a mixed solvent of phenol / tetrachloroethane (weight ratio 1/1) and measuring the number of seconds of dropping only a polymer solution having a concentration of 1.0 g / dl and a solvent at 30 ° C., the following formula (3) I asked more.

IV = ((1 + 4K _H η _sp ) 0.5-1) / (2K _H C) (3)
However, in Formula (3), it is (eta) _sp = ((eta) / (eta) ₀ ) -1, (eta) is a polymer solution fall time, (eta) ₀ is a solvent fall time, C is a polymer solution density | concentration (g / dl), K _H is a constant of Haggins and set to 0.33.

Titanium and group 2 metal concentration in PBT resin:
The PBT resin was wet-decomposed with high-purity sulfuric acid and nitric acid for electronic industry and measured using a high-resolution ICP-MS (Inductively Coupled Plasma-Mass Spectrometer) (manufactured by ThermoQuest).

Terminal carboxyl group concentration:
0.5 g of PBT resin or oligomer was dissolved in 25 ml of benzyl alcohol and titrated using a 0.01 mol / l benzyl alcohol solution of sodium hydroxide.

[Raw material of resin composition]
(A1) Polybutylene terephthalate resin:
It manufactured according to the following manufacture example.
A PBT resin was produced by the following method using the esterification step shown in FIG. 2 and the polycondensation step shown in FIG.
First, a 60 ° C. slurry mixed at a ratio of 1.80 mol of 1,4-butanediol with respect to 1.00 mol of terephthalic acid was passed through the raw material supply line 1 from the slurry preparation tank in advance with an esterification rate of 99%. Was continuously fed to a reaction tank A for esterification having a screw type stirrer filled with PBT oligomer of 40 kg / h. At the same time, the bottom component of the rectifying column C at 185 ° C. (98% by weight or more is 1,4-butanediol) is supplied at 20 kg / h from the recirculation line 2 and the catalyst at 65 ° C. is supplied from the titanium catalyst supply line 3 as a catalyst. A 6.0 wt% 1,4-butanediol solution of tetrabutyl titanate was fed at 99 g / h (30 ppm relative to the theoretical polymer yield). The water content in this catalyst solution was 0.2% by weight. A 6.0 wt% 1,4-butanediol solution of magnesium acetate tetrahydrate at 65 ° C. was fed as a catalyst at 62 g / h from the group 2 metal catalyst feed line 15 (15 ppm based on the theoretical polymer yield). The water content in this catalyst solution was 10.0% by weight.

  The internal temperature of the reaction tank A is 230 ° C., the pressure is 78 kPa, and the produced water, tetrahydrofuran and excess 1,4-butanediol are distilled from the distillation line 5, and the high boiling component and low boiling point are distilled in the rectification column C. Separated into ingredients. The high-boiling component at the bottom of the column after the system is stabilized is 98% by weight or more of 1,4-butanediol, and a part of the high-boiling component through the extraction line 8 so that the liquid level of the rectifying column C is constant. Extracted outside. On the other hand, the low boiling component was extracted from the top of the column in the form of gas, condensed by the condenser G, and extracted from the extraction line 13 to the outside so that the liquid level of the tank F was constant.

  A certain amount of the oligomer generated in the reaction tank A was extracted from the extraction line 4 using the extraction pump B, and the liquid level was controlled so that the average residence time of the liquid in the reaction tank A was 150 minutes. The oligomer extracted from the extraction line 4 was continuously supplied to the first polycondensation reaction tank a shown in FIG. After the system was stabilized, the esterification rate of the oligomer collected at the outlet of the reaction tank A was 96.5%.

  The internal temperature of the first polycondensation reaction tank a was 240 ° C., the pressure was 2.1 kPa, and the liquid level was controlled so that the residence time was 120 minutes. An initial polycondensation reaction was performed while extracting water, tetrahydrofuran and 1,4-butanediol from a vent line L2 connected to a decompressor (not shown). The extracted reaction liquid was continuously supplied to the second polycondensation reaction tank d.

  The internal temperature of the second polycondensation reaction tank d is 240 ° C., the pressure is 130 Pa, the liquid level is controlled so that the residence time is 85 minutes, and water is supplied from a vent line L4 connected to a decompressor (not shown). Further, the polycondensation reaction was advanced while extracting tetrahydrofuran and 1,4-butanediol. The obtained polymer was continuously extracted in the form of a strand from the die head g through the extraction line L3 by the extraction gear pump e, and was cut with a rotary cutter h to obtain PBT resin pellets. The obtained PBT resin pellets were subjected to solid-phase polymerization under a reduced pressure of 205 ° C. and 0.133 kPa or less in a double-conical blender (with an internal volume of 100 l). The pellet was taken out when the value reached. The obtained PBT resin had an intrinsic viscosity [η] = 0.85 dl / g, a titanium content of 30 ppm, a magnesium content of 15 ppm, and a terminal carboxyl group concentration of 15 μeq / g.

(A2) Polyamide 6: Product name “Novamid (registered trademark) 1013J” manufactured by Mitsubishi Engineering Plastics Co., Ltd. Viscosity: 138 ml / g (measured in accordance with ISO 307 standard at a temperature of 25 ° C., 96 wt% sulfuric acid and a polyamide resin concentration of 0.5 wt%)
(A3) Polyamide MXD6: manufactured by Mitsubishi Gas Chemical Co., Ltd., trade name “Polyamide MXD6 # 6000”, a polyamide resin produced from metaxylylenediamine and adipic acid. Apparent melt viscosity 1600 poise (capillary rheometer (“Capillograph 1C” manufactured by Toyo Seiki Co., Ltd.), capillary L / D = 30 mm / 1 mm, temperature 280 ° C., shear rate 100 sec −1)

(B1) Flat cross-section glass fiber: Product name “CSG3PA830” manufactured by Nittobo Co., Ltd., oval cross section, long diameter (D2) = 28 μm, short diameter (D1) = 7 μm, flatness ratio 4. It has a cross-sectional area corresponding to a fiber diameter of 18 μm. Cut length 3mm, E glass, refractive index (nd) 1.55
(B2) Flat cross-section glass fiber: manufactured by Nittobo Co., Ltd., trade name “CSH3PA860”, bowl-shaped cross section, long diameter (D2) = 20 μm, short diameter (D1) = 10 μm, flatness ratio 2. It has a cross-sectional area corresponding to a fiber diameter of 18 μm. Cut length 3mm, E glass, refractive index (nd) 1.55
(B3) Circular cross-section glass fiber: manufactured by Nippon Electric Glass Co., Ltd., trade name “ECT03T-187”. Fiber diameter 13 μm, cut length 3 mm, E glass, refractive index (nd) 1.55
(B4) Circular cross-section glass fiber: manufactured by Nippon Electric Glass Co., Ltd., “trade name: ECS03T-289”, fiber diameter 13 μm, cut length 3 mm, E glass, refractive index (nd) 1.55

(C) Colorant master batch: manufactured by Orient Chemical Industry Co., Ltd., trade name “eBIND LTW-8950C”. A master batch of methine oil-soluble dye and polybutylene terephthalate resin.

Antioxidant: Pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], “trade name: Irganox 1010”, molecular weight 1178, manufactured by Ciba Specialty Chemicals.

[Method for producing thermoplastic resin composition (II)]
Carbon black (manufactured by Mitsubishi Chemical Co., Ltd., product number: MA600B) was blended in the resin composition of each of Examples and Comparative Examples described later at a ratio of 0.6 part by weight with respect to 100 parts by weight of the resin component. Using.

[Examples 1 to 6 and Comparative Examples 1 to 4]
The thermoplastic resins (A1) to (A3) and, if necessary, colorants and antioxidants were blended in the ratios shown in Table 1, and mixed for 20 minutes with a tumbler. Using a twin-screw extruder (“TEX30C” manufactured by Nippon Steel Co., Ltd., 9-barrel configuration) with a cylinder temperature set to 250 ° C., the obtained raw material mixture is supplied from a hopper, and the glass of (B1) to (B4) The fibers were fed from the fifth block counted from the hopper by the side feed method and melt-kneaded. The evaluation mentioned above was performed using the obtained resin composition pellet. The evaluation results are shown in Table 1.

  As shown in Table 1, it was clarified that by using the flat glass fiber of the present invention, a resin composition with improved laser transmittance, excellent laser welding characteristics, and good mechanical strength can be obtained. (Examples 1-6). Further, by using the thermoplastic resin composition of the present invention, strong laser welding with other members can be easily performed.

  By using the thermoplastic resin composition of the present invention, the range of product thickness that can be welded is widened, the degree of freedom in product design can be increased, and the range of laser welding conditions such as laser irradiation intensity and scanning speed can be increased. It is possible to provide a molded product in which members are more firmly bonded to each other. Such molded products are widely used industrially, and can be suitably used particularly for products such as vehicle electrical parts, sensor parts, connector parts, and hollow parts for vehicles, and their utility value is extremely high. Is.

(Figure 1)
1 Test piece 1
2 Test piece 2
3 Laser irradiation points

(Fig. 2) and (Fig. 3)
1 Raw Material Supply Line 2 Recirculation Line 3 Titanium Catalyst Supply Line 4 Extraction Line 5 Distillation Line 6 Extraction Line 7 Circulation Line 8 Extraction Line 9 Gas Extraction Line 10 Condensate Line 11 Extraction Line 12 Circulation Line 13 Extraction Outlet line 14 Vent line 15 Group 1 metal catalyst and / or Group 2 metal catalyst supply line A Reaction tank B Extraction pump C Rectification tower D Pump E Pump F Tank G Capacitor L1 Extraction line L2 Vent line L3 Extraction line L4 Vent line a First polycondensation reaction tank c Extraction gear pump d Second polycondensation reaction tank e Extraction gear pump g Die head h Rotary cutter

The present invention has been completed based on the above findings, and the gist thereof is as follows.
(1) at least one of the thermoplastic resin (A) 100 parts by weight of containing polyester resins, fiberglass fiber length direction perpendicular cross-section is a flat rate of 1.5 or more flat shape by the following formula (B) A thermoplastic resin composition for laser welding comprising 10 to 150 parts by weight , wherein the polyester resin is obtained using a titanium compound, a Group 1 metal compound and / or a Group 2 metal compound as a catalyst. The polybutylene terephthalate resin has a titanium concentration of 80 ppm or less as a titanium atom, and the contained group 1 metal compound and / or group 2 metal compound concentration is 50 ppm or less in terms of each metal atom. A thermoplastic resin composition for laser welding, which is characterized by being.
Flatness ratio = major axis (D2) of glass fiber section / minor axis (D1) of glass fiber section
(2) The thermoplastic resin composition for laser welding according to (1), wherein the flatness of the glass fiber (B) is 1.5 to 10.
(3) The thermoplastic resin composition for laser welding according to (1), wherein the flatness of the glass fiber (B) is 2.5 to 6.
(4) The laser welding thermoplastic resin composition according to any one of (1) to (3), wherein the cross-sectional shape of the glass fiber (B) is an oval, an ellipse, or a rectangle .
(5 ) The thermoplastic resin composition for laser welding according to any one of ( 1 ) to ( 4 ) , wherein the terminal carboxyl group concentration of the polybutylene terephthalate resin is 40 eq / ton or less .
(6 ) The thermoplastic resin composition for laser welding according to any one of (1) to ( 5 ), further comprising a colorant (C).
( 7 ) The thermoplastic resin composition for laser welding according to any one of (1) to ( 6 ), which is used for a member on the laser transmission side.
( 8 ) A member made of the laser-welded reinforced thermoplastic resin composition (I) according to any one of (1) to ( 7 ) and a member made of the resin composition (II) having laser absorbability, the resin A molded article formed by welding by irradiating a laser beam from the member side made of the composition (I).
( 9 ) A member made of the thermoplastic resin composition (I) for laser welding according to any one of (1) to ( 7 ) and a member made of the thermoplastic resin composition (II) having laser absorption, The manufacturing method of the molded article including the process of irradiating and welding a laser beam from the member side which consists of resin composition (I).

[Method for producing thermoplastic resin composition (II)]
Carbon black (manufactured by Mitsubishi Chemical Corporation, product number: MA600B) is added to the resin compositions of Examples , Comparative Examples , Reference Examples, and Reference Comparative Examples , which will be described later, to 0.6 parts by weight with respect to 100 parts by weight of the resin component. What was mix | blended in the ratio of was used.

[Examples 1 to 4, Reference Examples 1 and 2, and Comparative Examples 1 and 2, Reference Comparative Examples 1 and 2 ]
The thermoplastic resins (A1) to (A3) and, if necessary, colorants and antioxidants were blended in the ratios shown in Table 1, and mixed for 20 minutes with a tumbler. Using a twin-screw extruder (“TEX30C” manufactured by Nippon Steel Co., Ltd., 9-barrel configuration) with a cylinder temperature set to 250 ° C., the obtained raw material mixture is supplied from a hopper, and the glass of (B1) to (B4) The fibers were fed from the fifth block counted from the hopper by the side feed method and melt-kneaded. The evaluation mentioned above was performed using the obtained resin composition pellet. The evaluation results are shown in Table 1.

As shown in Table 1, it was clarified that by using the flat glass fiber of the present invention, a resin composition with improved laser transmittance, excellent laser welding characteristics, and good mechanical strength can be obtained. (Examples 1-4 ). Further, by using the thermoplastic resin composition of the present invention, strong laser welding with other members can be easily performed.

Claims (15)

A glass fiber whose cross section perpendicular to the fiber length direction is a flat shape having a flatness ratio of 1.5 or more according to the following formula with respect to 100 parts by weight of the thermoplastic resin (A) containing at least one polyester resin or polyamide resin ( B) A thermoplastic resin composition for laser welding, comprising 10 to 150 parts by weight.
Flatness ratio = major axis (D2) of glass fiber section / minor axis (D1) of glass fiber section   The thermoplastic resin composition for laser welding according to claim 1, wherein the flatness of the glass fiber (B) is 1.5 to 10.   The thermoplastic resin composition for laser welding according to claim 1, wherein the flatness of the glass fiber (B) is 2.5 to 6.   The thermoplastic resin composition for laser welding according to any one of claims 1 to 3, wherein the cross-sectional shape of the glass fiber (B) is an oval, an ellipse, or a rectangle.   The thermoplastic resin composition for laser welding according to any one of claims 1 to 4, wherein the polyester resin is a polybutylene terephthalate resin.   The thermoplastic resin composition for laser welding according to claim 5, wherein the polybutylene terephthalate resin is obtained using a titanium compound as a catalyst, and the concentration of contained titanium is 80 ppm or less as titanium atoms.   The thermoplastic resin composition for laser welding according to claim 5 or 6, wherein the terminal carboxyl group concentration of the polybutylene terephthalate resin is 40 eq / ton or less.   The thermoplastic resin composition for laser welding according to any one of claims 1 to 7, wherein at least one monomer constituting at least one polyamide resin contains an aromatic ring.   The polyamide resin contains at least one selected from a salt consisting of an aliphatic diamine and an aromatic dicarboxylic acid and a salt consisting of an aromatic diamine and an aliphatic dicarboxylic acid as the structural unit (a). The thermoplastic resin composition for laser welding according to any one of the above.   The thermoplastic resin composition for laser welding according to claim 9, wherein the structural unit (a) is 30 mol% or more of all structural units of the polyamide resin.   The polyamide resin contains at least one selected from the salt consisting of hexamethylenediamine and terephthalic acid and / or isophthalic acid and the salt consisting of xylylenediamine and adipic acid as the structural unit (a). 10. The thermoplastic resin composition for laser welding according to any one of 1 to 10.   Furthermore, the thermoplastic resin composition for laser welding of any one of Claims 1-11 formed by mix | blending a coloring agent (C).   The thermoplastic resin composition for laser welding according to any one of claims 1 to 12, which is used for a member on a laser transmission side.   A member made of the laser-welded reinforced thermoplastic resin composition (I) according to any one of claims 1 to 13 and a member made of the laser-absorbing resin composition (II), the resin composition ( A molded product formed by welding by irradiating a laser beam from the member side consisting of I).   A member comprising the thermoplastic resin composition (I) for laser welding according to any one of claims 1 to 13 and a member comprising the thermoplastic resin composition (II) having laser absorption, and the resin composition. The manufacturing method of the molded article including the process of irradiating and welding a laser beam from the member side which consists of (I).

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