JP2007154068A - Resin composition for black laser marking and molded article therefrom - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyamide resin composition for a black laser marking which can provide a clear black laser marking and is excellent in toughness and rigidity. <P>SOLUTION: This polyamide resin composition for a black laser marking comprises: (A) 40 to 90% by weight of a polyamide resin; (B) 10 to 60% by weight of a polyphenylene sulfide resin; and (C) 0.3 to 9.0 parts by weight of zinc borate having no hydrate, relative to the total 100 parts by weight of (A) and (B). <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a resin composition capable of realizing clear printing by black laser marking and a molded product thereof.

  Conventionally, polyamide resins are excellent in mechanical properties such as tensile and bending strength and elastic modulus, and also have good heat resistance, chemical resistance, and flame resistance. Widely used in parts and machine parts. However, since the polyamide resin originally tends to foam against local heating by a laser, white laser marking was possible, but it was difficult to obtain a clear black laser marking. On the other hand, as resin materials capable of black laser marking, resins such as ABS resin and polyester have been used. However, the ABS resin is unsuitable for increasing the rigidity with an inorganic reinforcing agent, has low heat resistance, and is easily combustible, so that its use range is limited. Similarly, polyester capable of black laser marking has low toughness and has a limited range of use. Therefore, there has been a demand for a thermoplastic resin composition capable of black laser marking and having excellent mechanical properties such as toughness and rigidity.

For example, Patent Document 1 proposes a resin composition for laser marking in which alumina hydrate is blended with a resin, but due to local overheating by a laser, the alumina hydrate releases water and foams the resin. There was a drawback that a clear black laser marking could not be obtained. Patent Document 2 proposes a resin composition for laser marking in which zinc borate hydrate is blended with a thermoplastic resin. Similarly, the zinc borate hydrate releases water, and a clear black laser marking. There was a disadvantage that could not be obtained.
Japanese Patent Laying-Open No. 2005-162913 (Claim 1) JP-A-6-136273 (Claim 1)

  An object of the present invention is to provide a polyamide resin composition for black laser marking, which enables clear black laser marking and is excellent in toughness and rigidity.

  Therefore, the present inventors have intensively studied to solve the above problems, and as a result, found that the object can be achieved as a result of blending polyphenylene sulfide resin and zinc borate having no hydrate with polyamide resin. The invention has been reached.

That is, the present invention
(1) (A) A resin composition comprising 40 to 90% by weight of a polyamide resin and (B) 10 to 60% by weight of a polyphenylene sulfide resin, wherein the total amount of (A) and (B) is 100 parts by weight. (C) a polyamide resin composition for black laser marking, comprising 0.3 to 9.0 parts by weight of zinc borate having no hydrate,
(2) The black laser as described in (1), wherein 10 to 140 parts by weight of (D) inorganic filler is contained with respect to a total of 100 parts by weight of (A) polyamide resin and (B) polyphenylene sulfide resin. Polyamide resin composition for marking,
(3) The polyamide resin composition for black laser marking according to (1) or (2), wherein the (A) polyamide resin is an aliphatic polyamide resin,
(4) The polyamide resin composition for black laser marking according to (3), wherein the aliphatic polyamide resin is at least one selected from nylon 6, nylon 66, nylon 6/66, and a mixture thereof. ,
(5) The polyamide resin composition for black laser marking according to (1) or (2), wherein the (A) polyamide resin is a semi-aromatic polyamide resin,
(6) The semi-aromatic polyamide resin is at least one selected from nylon 6I / 66, nylon 6T / 66, nylon 66 / 6I / 6, nylon 6T / 6I and a mixture thereof ( 5) The polyamide resin composition for black laser marking according to
(7) The resin composition according to any one of (1) to (6), wherein (D) the inorganic filler is a glass fiber,
(8) A molded article comprising the polyamide resin composition for black laser marking according to any one of (1) to (7),
(9) Black laser marking method using the molded article according to (8),
Consists of.

  The resin composition of the present invention expresses a very excellent black laser marking property by blending a polyamide resin with a polyphenylene sulfide resin, zinc borate having no water of hydration at a specific ratio, and good rigidity, Realize toughness at the same time.

  Embodiments of the present invention will be described below. In the present invention, “weight” means “mass”.

  The (A) polyamide resin used in the present invention is a polyamide mainly composed of amino acids, lactams or diamines and dicarboxylic acids. Representative examples of the main constituents include amino acids such as 6-aminocaproic acid, 11-aminoundecanoic acid, 12-aminododecanoic acid and paraaminomethylbenzoic acid, lactams such as ε-caprolactam and ω-laurolactam, and tetramethylenediamine. , Hexamethylenediamine, 1,5-pentanediamine, 2-methylpentamethylenediamine, nonamethylenediamine, undecamethylenediamine, dodecamethylenediamine, 2,2,4- / 2,4,4-trimethylhexamethylenediamine, 5-methylnonamethylenediamine, metaxylenediamine, paraxylenediamine, 1,3-bis (aminomethyl) cyclohexane, 1,4-bis (aminomethyl) cyclohexane, 1-amino-3-aminomethyl-3,5 5-trimethylsick Fats such as sun, bis (4-aminocyclohexyl) methane, bis (3-methyl-4-aminocyclohexyl) methane, 2,2-bis (4-aminocyclohexyl) propane, bis (aminopropyl) piperazine, aminoethylpiperazine , Cycloaliphatic, aromatic diamines, and adipic acid, speric acid, azelaic acid, sebacic acid, dodecanedioic acid, terephthalic acid, isophthalic acid, 2-chloroterephthalic acid, 2-methylterephthalic acid, 5-methylisophthalic acid Examples include aliphatic, alicyclic, and aromatic dicarboxylic acids such as acid, 5-sodium sulfoisophthalic acid, 2,6-naphthalenedicarboxylic acid, hexahydroterephthalic acid, and hexahydroisophthalic acid. Nylon homopolymers or copolymers derived from It can be used in the form of people alone or as a mixture.

  In the present invention, a particularly useful polyamide resin is a polyamide resin having a melting point of 150 ° C. or more and excellent in heat resistance and strength. Specific examples include polycaproamide (nylon 6), polyhexamethylene adipamide. (Nylon 66), polypentamethylene adipamide (nylon 56), polytetramethylene adipamide (nylon 46), polyhexamethylene sebamide (nylon 610), polyhexamethylene dodecamide (nylon 612), polyundecane Aliphatic polyamide resins such as amide (nylon 11), polydodecanamide (nylon 12), polycaproamide / polyhexamethylene adipamide copolymer (nylon 6/66), polycaproamide / polyhexamethylene terephthalamide copolymer (nylon) 6 / 6T), polyhexa Tylene adipamide / polyhexamethylene isophthalamide copolymer (nylon 66 / 6I), polyhexamethylene terephthalamide / polyhexamethylene isophthalamide copolymer (nylon 6T / 6I), polyhexamethylene terephthalamide / polydodecanamide copolymer (nylon 6T / 12) , Polyhexamethylene adipamide / polyhexamethylene terephthalamide / polyhexamethylene isophthalamide copolymer (nylon 66 / 6T / 6I), polyxylylene adipamide (nylon XD6), polyhexamethylene terephthalamide / poly-2- Semi-aromatic polyamide resins such as methyl pentamethylene terephthalamide copolymer (nylon 6T / M5T), polynomethylene terephthalamide (nylon 9T), and the like Mixtures of the like.

  Particularly preferred (A) polyamide resin is at least one selected from nylon 6, nylon 66, nylon 6/66 and mixtures thereof for aliphatic polyamide resin, and nylon 6I / 66, nylon for semi-aromatic polyamide resin. Examples thereof include at least one selected from 6T / 66, nylon 66 / 6I / 6, nylon 6T / 6I, and mixtures thereof. Furthermore, it is practically preferable to use (A) a polyamide resin as a mixture of an aliphatic polyamide resin and a semi-aromatic polyamide resin according to required properties such as moldability and compatibility.

  The degree of polymerization of these polyamide resins is not particularly limited, but the relative viscosity measured at 25 ° C. in a 98% concentrated sulfuric acid solution having a sample concentration of 0.01 g / ml is in the range of 1.5 to 7.0. Is preferable, more preferably 1.5 to 4.0, and particularly preferably 1.8 to 3.2.

  The (B) polyphenylene sulfide resin (hereinafter abbreviated as PPS resin) used in the present invention is a polymer having a repeating unit represented by the following structural formula (I):

From the viewpoint of heat resistance, the polymer preferably contains 70 mol% or more, more preferably 90 mol% or more of a polymer containing a repeating unit represented by the above structural formula. In addition, about 30 mol% or less of the repeating unit of PPS may be composed of a repeating unit having the following structure.

  The melt viscosity of the PPS resin used in the present invention is not particularly limited as long as melt kneading is possible. However, the melt flow rate measured at 316 ° C. under a load of 5000 g is 10 to 20,000 g / 10 min. It is preferable that it is 20 to 10,000 g / 10min.

  PPS satisfying such properties is a method for obtaining a polymer having a relatively low molecular weight obtained by a production method represented by Japanese Patent Publication No. 45-3368, or Japanese Patent Publication No. 52-12240 and Japanese Patent Publication No. 61-7332. It can be produced by a known method such as a method for obtaining a polymer having a relatively large molecular weight described in the publication.

  The PPS resin obtained as described above may be used as it is, or it may be used for crosslinking / polymerization by heating in air, heat treatment under an inert gas atmosphere such as nitrogen or reduced pressure, organic solvent, hot water. It is also possible to use after washing with an acid aqueous solution or the like.

  In the case of washing with an organic solvent, the organic solvent to be used is not particularly limited as long as it does not have an action of decomposing PPS. For example, N-methylpyrrolidone, dimethylformaldehyde, dimethylacetamide, 1,3-dimethylimidazolidinone Nitrogen-containing polar solvents such as hexamethylphosphoramide and piperazinones, sulfoxide and sulfone solvents such as dimethyl sulfoxide, dimethyl sulfone and sulfolane, ketone solvents such as acetone, methyl ethyl ketone, diethyl ketone and acetophenone, dimethyl ether and dipropyl ether -Ether solvents such as tellurium, dioxane, tetrahydrofuran, chloroform, methylene chloride, trichloroethylene, ethylene dichloride, perchloroethylene, monochloroethane, dichloroethane, tetrachloro Halogen solvents such as ethane, perchloroethane, chlorobenzene, methanol, ethanol, propanol, butanol, pentanole, ethylene glycol, propylene glycol, phenol, cresol And alcohol / phenol solvents such as polyethylene glycol and polypropylene glycol, and aromatic hydrocarbon solvents such as benzene, toluene and xylene.

  There is no restriction | limiting in particular also about washing | cleaning temperature, Usually, about normal temperature-about 300 degreeC are selected. In the case of washing with an acid aqueous solution, the acid to be used is not particularly limited as long as it does not have an action of decomposing PPS, and examples thereof include acetic acid, hydrochloric acid, sulfuric acid, phosphoric acid, silicic acid, carbonic acid, and propyl acid. Moreover, it can also be used after performing various treatments such as activation with a functional group-containing compound such as an acid anhydride group, an epoxy group, or an isocyanate group. In the method for producing pellets of the present invention, the above PPS resin is used as it is or a PPS resin composition in which it is blended with other components is subjected to melt extrusion.

  Although there is no restriction | limiting in particular as another component with which it mix | blends with the said PPS resin, In the range which does not impair the effect of this invention, normal additives, such as a silane compound, a mold release agent, and a crystal nucleating agent, and a small amount of modified olefins System resins or other polymers can be added.

It is necessary for the polyamide resin composition of the present invention to contain (C) zinc borate having no hydrate in order to have black laser marking properties. The zinc borate having no hydrate (C) used in the present invention is 2ZnO.3B ₂ O ₃ and is obtained by baking zinc borate having a hydrate to remove the hydrate. It is done. Examples of zinc borate having a hydrate include 4ZnO · B ₂ O ₃ · H ₂ O, 2ZnO · 3B ₂ O ₃ · 3.5H ₂ O, and the like.

  In the polyamide resin composition of the present invention, (A) the polyamide resin needs to be 40 to 90% by weight in a total of 100 parts by weight of (A) the polyamide resin and (B) the polyphenylene sulfide resin. If it is 40% by weight or less, the toughness of the molded product is impaired, and if it is 90% by weight or more, the black laser marking property is impaired. Preferably it is the range of 50 to 85 weight%. Moreover, (B) polyphenylene sulfide resin needs to be 10 to 60 weight%. If it is 60% by weight or more, the toughness of the molded product is impaired, and if it is 10% by weight or less, the black laser marking property is impaired. Preferably it is the range of 15-50 weight%.

  In the present invention, (C) zinc borate having no hydrate needs to be 0.3 to 9.0 parts by weight with respect to 100 parts by weight of (A) and (B) in total. If it is 0.3 parts by weight or less, the black laser marking property is impaired, and if it is 9.0 parts by weight or more, the black laser marking property is excellent, but the mechanical properties of the molded product are impaired. Preferably it is the range of 0.4-8.0 weight part.

  In the present invention, in order to increase the strength of the polyamide resin composition, it is preferable to further contain (D) an inorganic filler. The inorganic filler (D) used in the present invention is not particularly limited, but it is preferable to use a fibrous inorganic filler in terms of the properties as a reinforcing agent, specifically, glass fiber, stainless steel fiber. , Metal fibers such as aluminum fibers and brass fibers, organic fibers such as aromatic polyamide fibers, gypsum fibers, ceramic fibers, asbestos fibers, zirconia fibers, alumina fibers, silica fibers, titanium oxide fibers, silicon carbide fibers, rock wool, titanium Examples thereof include fibrous and whisker-like fillers such as potassium acid whisker, silicon nitride whisker, and wollastonite. In the filler, glass fiber and wollastonite are preferably used, and more preferably glass fiber.

  The type of glass fiber is not particularly limited as long as it is generally used for reinforcing a resin, and can be selected from, for example, a long fiber type, a short fiber type chopped strand, a milled fiber, or the like. Moreover, said filler can also be used in combination of 2 or more types. Note that the surface of the filler used in the present invention is preliminarily treated with an organic onium ion in the case of a coupling agent such as a silane coupling agent or a titanate coupling agent, or other surface treatment agent, or a swellable layered silicate. The treatment is preferable in terms of obtaining a higher mechanical strength. The glass fiber may be coated or bundled with a thermoplastic resin such as an ethylene / vinyl acetate copolymer or a thermosetting resin such as an epoxy resin.

  (D) It is preferable that the compounding quantity of an inorganic filler is 10-140 weight part with respect to a total of 100 weight part of (A) and (B). If the amount is less than 10 parts by weight, the mechanical properties are not improved. If the amount exceeds 140 parts by weight, not only the fluidity during molding is impaired, but also the improvement of the mechanical properties is not recognized. The amount of 15 to 130 parts by weight is more preferred from the balance of fluidity and mechanical properties during molding.

  In addition, the polyamide resin of the present invention further includes copper-based heat stabilizers, hindered phenol-based, phosphorus-based, sulfur-based antioxidants, heat stabilizers, ultraviolet absorbers, and the like within a range that does not impair the object of the present invention. One or more usual additives such as flame retardants, lubricants, mold release agents, antistatic agents, and colorants including dyes and pigments can be added.

  The method for producing the polyamide resin composition of the present invention is not particularly limited. For example, polyamide resin, polyphenylene sulfide resin, zinc borate without hydrate, inorganic filler is kneaded in a single or twin screw extruder or kneader. Examples thereof include a melt kneading method at a temperature of 220 to 330 ° C. using a machine.

  The polyamide resin composition of the present invention can be easily molded by ordinary methods such as injection molding and extrusion molding, and the obtained molded product is excellent in black laser marking properties and mechanical properties such as rigidity and toughness. .

  Black laser marking can be performed on the molded article made of the resin composition of the present invention by any method. For example, a YAG laser or a carbon dioxide laser can be used, but the present invention is not limited to these.

  Since the polyamide resin composition of the present invention has excellent black laser marking properties, it can be used for mobile phones, PHS, liquid crystal televisions, plasma displays, PDAs, small televisions, radios, breaker covers, breaker bases, electromagnetic switch covers, notebook computers, personal computers, Mouse, printer, scanner, memory device, computer peripheral device, video deck, DVD deck, CD deck, MD deck, DAT deck, amplifier, cassette deck, portable CD player, portable MD player, camera, digital camera, binoculars, microscope, Telescopes, watches, home phones, office phones, toys, medical equipment, rice cooker parts, microwave oven parts, acoustic parts, lighting parts, refrigerator parts, air conditioner parts, facsimile parts, photocopier parts, building material parts, furniture parts For such as , And it can be used in their nameplate portion.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated further in detail, this invention is not limited by these. Measurement methods used in Examples and Comparative Examples are shown below.

(1) Material strength It measured according to the following standard methods.
Tensile strength: ISO 527-1, -2
Toughness (Charpy impact strength): ISO 179

(2) Evaluation of black laser marking property An 80 × 80 × 3 (mm) mirror-polished square plate (film gate) was injection-molded, and the surface of the obtained square plate was subjected to the method shown in Reference Example 4 according to “Toray Resin”. "5mm x 5mm per character" is printed with laser marking, and the printed surface is scanned with a scanner GT-7700U manufactured by Seiko Epson Corporation. Read de! ! Using Coco (Version 9.00), we observed how many times it was correctly recognized. The evaluation criteria are as follows.
◎: Recognized 5 times out of 5 ○: Recognized 4 times out of 5 △: Recognized 3 times out of 5 times ×: Recognized 2 times out of 5 times

Reference Example 1 Production of polyphenylene sulfide resin In an autoclave equipped with a stirrer, 6.005 kg (25 mol) of sodium sulfide nonahydrate, 0.205 kg (2.5 mol) of sodium acetate and 5 kg of NMP were charged, and the temperature was gradually raised to 205 ° C. through nitrogen. Warm and distill 3.6 liters of water. Next, after cooling the reaction vessel to 180 ° C., 3.719 kg (25.3 mol) of 1,4-dichlorobenzene and 3.7 kg of NMP were added, sealed under nitrogen, heated to 270 ° C., heated to 270 ° C. Reacted for 2.5 hours. After cooling, the reaction product was washed 5 times with warm water, then heated to 100 ° C., poured into 10 kg of NMP, stirred for about 1 hour, filtered, and washed several times with hot water. This was poured into 25 liters of an acetic acid aqueous solution of pH 4 heated to 90 ° C., and stirred for about 1 hour, filtered, washed with ion-exchanged water at about 90 ° C. until the pH of filtration became 7, It dried under reduced pressure at 80 degreeC for 24 hours, and obtained the polyphenylene sulfide resin of MFR600 (g / 10min). In addition, MFR was measured by the method of 316 degreeC and the load 5000g.

Reference Example 2 Production of Copolymer Polyamide A 66 / 6I copolymer polyamide having a copolymerization ratio of 80% by weight was produced by the following polymerization method. Hexamethylenediamine and adipic acid equimolar salt Hexamethylenediamine and isophthalic acid equimolar salt were added in the ratios shown in Table 1, respectively, and the same amount of pure water as the total amount of raw materials added was added. After substituting with ₂ , the process was started while stirring, and the final temperature reached 270 ° C. while adjusting the can internal pressure to a maximum of 20 kg / cm ² . The polymer discharged into the water bath was pelletized with a strand cutter.

Reference Example 3 Preparation of Molded Product Test products for tensile strength and Charpy impact strength used in Examples and Comparative Examples were prepared by the following method. According to ISO1874-2, an injection molding machine PS60 manufactured by Nissei Plastic Industry Co., Ltd., cylinder temperature 300 ° C., mold surface temperature 80 ° C., screw rotation speed 150 rpm, parallel part flow rate 200 mm / second, injection / cooling = 20/10 Test pieces of ISO Type-A and Type-B standards were molded under the conditions of seconds. The test piece for laser marking property evaluation was injection-molded with a 80 × 80 × 3 (mm) mirror-polished square plate (film gate) under the same conditions, injection / cooling = 10/10 seconds.

Reference Example 4 Laser Marking Method Laser marking on the test specimens for evaluation used in Examples and Comparative Examples was performed by the following method. Using an RSM30D Nd; YAG laser device manufactured by Roffin Basel Japan Co., Ltd., the laser marking distance was 0.1 mm, the output was 30 kW, the current value was 32 A, the frequency was 6000 Hz, and the marking speed was 400 mm / sec.

Example 1
(A) Nylon 6 resin [manufactured by Toray Industries, Inc .: trade name CM1017] as the polyamide resin, (B) polyphenylene sulfide resin produced by the polymerization method shown in Reference Example 1, and (C) having no hydrate Zinc borate (chemical formula 2ZnO.3B ₂ O ₃ ) [made by Borax: FireBreak500] at the ratio shown in Table 1 and using a twin screw extruder (Toshiba Machine: TEM58) at a cylinder set temperature of 300 ° C. and screw rotation (A), (B), and (C) are top-fed (base feed) under the condition of several 200 rpm, melted and kneaded, then formed into a strand gut, cooled in a cooling bath, and granulated with a cutter. And pellets were obtained. The obtained pellets were molded by the method shown in Reference Example 3, and various characteristics were examined by the measurement methods described above. The results are shown in Table 1.

Examples 2 and 3
Except that (A), (B), and (C) are parts by weight shown in Table 1, pellets and molded products were obtained in the same manner as in Example 1, and various properties were examined. The results are shown in Table 1.

Example 4
(A) Pellets and molded products were obtained in the same manner as in Example 1 except that nylon 66 resin [manufactured by Toray Industries, Inc .: trade name CM3007] was used as the polyamide resin, and various characteristics were examined. The results are shown in Table 1.

Examples 5 and 6
Except that (A), (B), and (C) are parts by weight shown in Table 1, pellets and molded products were obtained in the same manner as in Example 4, and various characteristics were examined. The results are shown in Table 1.

Examples 7, 8, and 9
Except that (A), (B), and (C) are parts by weight shown in Table 2, pellets and molded products were obtained in the same manner as in Example 1, and various properties were examined. The results are shown in Table 2.

Examples 10, 11, 12
Except that (A), (B), and (C) are parts by weight shown in Table 2, pellets and molded products were obtained in the same manner as in Example 4, and various properties were examined. The results are shown in Table 2.

Examples 13, 14, 15, 16, 17, 18
(A), (B), (C) using a twin screw extruder (manufactured by Toshiba Machine Co., Ltd .: TEM58), top feed (base feed) under conditions of a cylinder set temperature of 300 ° C. and a screw rotation speed of 200 rpm (D) As an inorganic reinforcing material, glass fiber [manufactured by Nippon Sheet Glass Co., Ltd .: trade name TP-67] is used as a side feed, melt-kneaded at a ratio shown in Table 3, and then a strand-like gut is formed. After cooling with a cooling bath, it was granulated with a cutter to obtain pellets. The obtained pellets were molded by the method shown in Reference Example 3, and various characteristics were examined by the measurement methods described above. The results are shown in Table 3.

Example 19
(A) A pellet and a molded product were obtained in the same manner as in Example 14 except that the polyamide resin produced by the polymerization method of Reference Example 2 was used as the polyamide resin, and various characteristics were examined. The results are shown in Table 3.

Examples 20, 21, 22, 23, 24, 25, 26, 27
Except that (A), (B), (C), and (D) are parts by weight shown in Table 4, pellets and molded products were obtained in the same manner as in Example 13, and various properties were examined. The results are shown in Table 4.

Comparative Examples 1, 2, 5, 6, 7
Except that (A), (B), and (C) are parts by weight shown in Tables 5 and 6, pellets and molded products were obtained in the same manner as in Example 1, and various characteristics were examined. The results are shown in Tables 5 and 6.

Comparative Examples 3, 4, 8, 9, 10
Except that (A), (B), and (C) are parts by weight shown in Tables 5 and 6, pellets and molded products were obtained in the same manner as in Example 4, and various properties were examined. The results are shown in Tables 5 and 6.

Comparative Examples 11, 12, 15, 16, 17, 21, 22
Except that (A), (B), (C), and (D) are parts by weight shown in Tables 7, 8, and 9, pellets and molded products were obtained and various characteristics were examined in the same manner as in Example 13. The results are shown in Tables 7, 8, and 9.

Comparative Examples 13, 14, 18, 19, 20
Except that (A), (B), (C), and (D) are parts by weight shown in Tables 7, 8, and 9, pellets and molded products were obtained in the same manner as in Example 16, and various characteristics were examined. The results are shown in Tables 7, 8, and 9.

Comparative Example 23
(D) Examples except that zinc borate having no hydrate was changed to zinc borate having a hydrate (chemical formula 4ZnO · B ₂ O ₃ · H ₂ O) [manufactured by Borax, Inc., trade name: FireBreak415] In the same manner as in Example 14, pellets and molded products were obtained and various characteristics were examined. The results are shown in Table 9.

Comparative Example 24
(D) a zinc borate with no hydrate, zinc borate having hydrate (Formula _{2ZnO · 3B 2 O 3 · 3.5H} 2 O): except that the [Borax trade name FirebreakZB] is In the same manner as in Example 14, pellets and molded products were obtained, and various characteristics were examined. The results are shown in Table 9.

  By blending polyamide resin, polyphenylene sulfide resin, zinc borate without hydration water at a specific ratio from Examples 1 to 27 and Comparative Examples 1 to 24, a very clear black laser marking property is expressed, and It was confirmed that good rigidity and toughness can be realized at the same time.

Claims (9)

(A) A resin composition comprising 40 to 90% by weight of a polyamide resin and (B) 10 to 60% by weight of a polyphenylene sulfide resin, wherein (C) with respect to a total of 100 parts by weight of (A) and (B) ) A polyamide resin composition for black laser marking characterized by containing 0.3 to 9.0 parts by weight of zinc borate having no hydrate. 2. The polyamide for black laser marking according to claim 1, comprising (D) 10 to 140 parts by weight of an inorganic filler with respect to 100 parts by weight of the total of (A) polyamide resin and (B) polyphenylene sulfide resin. Resin composition. 3. The polyamide resin composition for black laser marking according to claim 1, wherein (A) the polyamide resin is an aliphatic polyamide resin. The polyamide resin composition for black laser marking according to claim 3, wherein the aliphatic polyamide resin is at least one selected from nylon 6, nylon 66, nylon 6/66, and a mixture thereof. (A) The polyamide resin for black laser marking according to claim 1 or 2, wherein the polyamide resin is a semi-aromatic polyamide resin. 6. The semi-aromatic polyamide resin is at least one selected from nylon 6I / 66, nylon 6T / 66, nylon 66 / 6I / 6, nylon 6T / 6I and mixtures thereof. Polyamide resin composition for black laser marking. (D) The resin composition according to any one of claims 1 to 6, wherein the inorganic filler is a glass fiber. A molded article comprising the polyamide resin composition for black laser marking according to any one of claims 1 to 7. A black laser marking method using the molded article according to claim 8.