JP6934756B2 - Resin composition, kit, manufacturing method of molded product and molded product - Google Patents

Description

The present invention relates to a resin composition, a kit, a method for producing a molded product, and a molded product. In particular, the present invention relates to a resin composition suitable for laser welding, a kit using the resin composition, a method for producing a molded product, and a molded product. The resin composition of the present invention is mainly used as a resin composition (light-transmitting resin composition) on the side that transmits light for laser welding.

Polyamide resin, which is a typical engineering plastic, is easy to process and is excellent in mechanical properties, electrical properties, heat resistance, and other physical and chemical properties. Therefore, it is widely used for vehicle parts, electrical / electronic equipment parts, other precision equipment parts, and the like. Recently, parts having complicated shapes are also manufactured from polyamide resin. For example, various welding techniques such as adhesive welding are used for bonding parts having a hollow portion such as an intake manifold. Vibration welding, ultrasonic welding, hot plate welding, injection welding, laser welding technology, etc. are used.

However, welding with an adhesive has problems of environmental load such as pollution of the surroundings in addition to the time loss until curing. It has been pointed out that ultrasonic welding and hot plate welding have problems such as damage to the product due to vibration and heat, and post-treatment due to the generation of abrasion powder and burrs. Further, injection welding often requires a special mold or molding machine, and further, there is a problem that it cannot be used unless the material has good fluidity.

On the other hand, laser welding includes a resin member having transparency (also referred to as non-absorbent or weakly absorbent) to laser light (hereinafter, may be referred to as "transmissive resin member") and absorbability to laser light. This is a method of joining the two resin members by contacting and welding the resin member having the above (hereinafter, may be referred to as “absorbent resin member”). Specifically, it is a method of irradiating a joint surface with laser light from the transmission resin member side to melt and join the absorbent resin member forming the joint surface with the energy of the laser light. Laser welding does not generate abrasion powder or burrs, causes less damage to the product, and since the polyamide resin itself is a material with relatively high laser transmittance, processing of polyamide resin products by laser welding technology is possible. It has been attracting attention recently.

The transmissive resin member is usually obtained by molding a light transmissive resin composition. As such a light-transmitting resin composition, Patent Document 1 states that (A) a reinforced filler having a refractive index of (B) 23 ° C. of 1.560 to 1.600 with respect to 100 parts by mass of a polyamide resin. A laser composition comprising 1 to 150 parts by mass of a polyamide resin, wherein at least one monomer constituting at least one of the above-mentioned (A) polyamide resins contains an aromatic ring. Welded polyamide resin compositions are described. In the examples of Patent Document 1, a resin composition in which a glass fiber and a colorant are blended in a blend of polyamide MXD6 and polyamide 66 or a blend of polyamide 6I / 6T and polyamide 6 is disclosed. ..

Japanese Unexamined Patent Publication No. 2008-308526

Here, in order to increase the elastic modulus of the resin composition (molded product), glass fibers are blended. Further, when increasing the toughness, it is conceivable to add an impact resistance improving agent (elastomer). However, if an impact resistance improver is added, light will not be transmitted. An object of the present invention is to solve such a problem, and to provide a resin composition having high toughness and excellent light transmission, and a kit or molded product using the resin composition. It is an object of the present invention to provide a manufacturing method and a molded product.

As a result of diligent studies by the present inventor based on the above problems, the above problems are solved by blending a predetermined xylylene-based polyamide resin and the polyamide resin 6 and adjusting the content of glass fibers. I found out that
Specifically, the above problems were solved by the following means <1>, preferably by <2> to <11>.
<1> Consists of a diamine-derived structural unit and a dicarboxylic acid-derived structural unit, 70 mol% or more of the diamine-derived structural unit is derived from xylylene diamine, and 70 mol% or more of the dicarboxylic acid-derived structural unit. Is a resin composition containing a xylylene-based polyamide resin derived from an α, ω-linear aliphatic dicarboxylic acid having 4 to 7 carbon atoms, a polyamide resin 6, glass fibers, and a light-transmitting dye. A resin composition containing the polyamide resin 6 in a proportion of 5 to 25% by mass of the resin composition, and the glass fibers in a proportion of 25 to 60% by mass of the resin composition.
<2> The resin composition according to <1>, wherein the L value of the resin composition is 5.0 or less.
<3> The resin composition according to <1> or <2>, wherein the total of the xylylene-based polyamide resin and the polyamide resin 6 accounts for 95% by mass or more of the resin component contained in the resin composition.
<4> The resin composition according to any one of <1> to <3>, which comprises the glass fiber in a proportion of 35 to 55% by mass of the resin composition.
<5> The resin composition according to any one of <1> to <4>, wherein the xylylenediamine contains metaxylylenediamine.
<6> The resin composition according to any one of <1> to <5>, wherein 70 mol% or more of the constituent unit derived from the dicarboxylic acid is derived from adipic acid.
<7> Consists of a diamine-derived structural unit and a dicarboxylic acid-derived structural unit, and 70 mol% or more of the diamine-derived structural unit is derived from m-xylylenediamine, and 90 mol% of the dicarboxylic acid-derived structural unit. The above is a resin composition containing a xylylene-based polyamide resin derived from adipic acid, a polyamide resin 6, glass fibers, and a light-transmitting dye. The polyamide resin 6 has a mass of 12 to 25 mass of the resin composition. The resin composition according to any one of <1> to <3>, which is contained in a proportion of%, and the glass fiber is contained in a proportion of 35 to 55% by mass of the resin composition.
<8> The resin composition according to any one of <1> to <7>, further containing talc.
<9> A kit comprising the resin composition according to any one of <1> to <8> and a light-absorbing resin composition containing a thermoplastic resin and a light-absorbing dye.
<10> A molded product obtained by molding the resin composition according to any one of <1> to <8>, and a light-absorbing resin composition containing a thermoplastic resin and a light-absorbing dye. A method for producing a molded product, which comprises laser welding the molded product.
<11> A molded product obtained by molding the resin composition according to any one of <1> to <8> or the kit according to <9>.

INDUSTRIAL APPLICABILITY According to the present invention, it has become possible to provide a resin composition having excellent light transmission while achieving high toughness, a kit using the resin composition, a method for producing a molded product, and a molded product.

Hereinafter, the contents of the present invention will be described in detail. In addition, in this specification, "~" is used in the meaning that the numerical values described before and after it are included as the lower limit value and the upper limit value.

The polyamide resin composition of the present invention is composed of a diamine-derived structural unit and a dicarboxylic acid-derived structural unit, and 70 mol% or more of the diamine-derived structural unit is derived from xylylene diamine and is a dicarboxylic acid-derived structural unit. A resin composition containing 70 mol% or more of a xylylene-based polyamide resin derived from α, ω-linear aliphatic dicarboxylic acid having 4 to 7 carbon atoms, a polyamide resin 6, glass fibers, and a light-transmitting dye. The polyamide resin 6 is contained in a proportion of 5 to 25% by mass of the resin composition, and the glass fiber is contained in a proportion of 25 to 60% by mass of the resin composition.
By combining the predetermined xylylene-based polyamide resin and the polyamide resin 6 in this way, a resin composition having excellent light transmission while achieving high toughness can be obtained. The polyamide resin 6 is known as an opaque resin, and it is surprising that the addition of the polyamide resin 6 improves the toughness of the obtained molded product and also improves the light transmittance. Although the reason for this is presumed, it is considered that the addition of these polyamides changed the morphology and contributed to the achievement of high light transmittance by changing the size and dispersion state of spherulites.

<Xylylene-based polyamide resin>
The xylylene-based polyamide resin used in the present invention is composed of a diamine-derived structural unit and a dicarboxylic acid-derived structural unit, and 70 mol% or more of the diamine-derived structural unit is derived from xylylene diamine and is derived from the dicarboxylic acid. More than 70 mol% of the constituent units are derived from α, ω-linear aliphatic dicarboxylic acid having 4 to 7 carbon atoms.

The xylylene-based polyamide resin preferably has 80 mol% or more, more preferably 90 mol% or more, still more preferably 95 mol% or more derived from xylylene diamine, and preferably 80 mol% or more of a dicarboxylic acid-derived constituent unit. More preferably 90 mol% or more, still more preferably 95 mol% or more, is derived from an α, ω-linear aliphatic dicarboxylic acid having 4 to 7 carbon atoms.

The xylylenediamine preferably contains at least one of paraxylylenediamine and metaxylylenediamine, more preferably contains metaxylylenediamine, and paraxylylenediamine (30 to 0 mol%) and metaxylylenediamine 70. It is more preferably containing ~ 100 mol%, further preferably containing 20 to 0 mol% of paraxylylenediamine and 80 to 100 mol% of metaxylylenediamine, and further preferably containing 10 to 0 mol% of paraxylylenediamine and metaxylylenedi. It is even more preferably contained 90-100 mol% of amine, even more preferably 5-0 mol% of paraxylylenediamine and 95-100 mol% of m-xylylenediamine.

Diamines other than xylylenediamine that can be used as the diamine component of the raw material of the xylylene-based polyamide resin include tetramethylenediamine, pentamethylenediamine, 2-methylpentanediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, and nona. Aliphatic diamines such as methylenediamine, decamethylenediamine, dodecamethylenediamine, 2,2,4-trimethyl-hexamethylenediamine, 2,4,4-trimethylhexamethylenediamine, 1,3-bis (aminomethyl) cyclohexane, 1,4-bis (aminomethyl) cyclohexane, 1,3-diaminocyclohexane, 1,4-diaminocyclohexane, bis (4-aminocyclohexyl) methane, 2,2-bis (4-aminocyclohexyl) propane, bis (amino) Examples of alicyclic diamines such as methyl) decalin and bis (aminomethyl) tricyclodecane, diamines having an aromatic ring such as bis (4-aminophenyl) ether, paraphenylenediamine, and bis (aminomethyl) naphthalene should be exemplified. Can be used with one or a mixture of two or more.
When a diamine other than xylylenediamine is used as the diamine component, it is less than 50 mol%, preferably 30 mol% or less, more preferably 1 to 25 mol%, and particularly preferably 5 of the constituent units derived from diamine. Use at a rate of ~ 20 mol%.

Examples of the α, ω-linear aliphatic dicarboxylic acid having 4 to 7 carbon atoms preferable to be used as the dicarboxylic acid component of the raw material of the polyamide resin include succinic acid, glutaric acid, adipic acid, and pimelic acid. Two or more types can be mixed and used, but among these, adipic acid is preferable because the melting point of the polyamide resin is in an appropriate range for molding.

Examples of the dicarboxylic acid component other than the α, ω-linear aliphatic dicarboxylic acid having 4 to 7 carbon atoms include α, ω-linear aliphatic dicarboxylic acid having 8 or more carbon atoms such as suberic acid, azelaic acid, and sebacic acid. , Isophthalic acid, terephthalic acid, orthophthalic acid and other phthalic acid compounds, 1,2-naphthalenedicarboxylic acid, 1,3-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 1,6 Naphthalenes such as isomers such as −naphthalenedicarboxylic acid, 1,7-naphthalenedicarboxylic acid, 1,8-naphthalenedicarboxylic acid, 2,3-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, and 2,7-naphthalenedicarboxylic acid. Examples thereof include dicarboxylic acids, and one type or a mixture of two or more types can be used.
When a dicarboxylic acid other than α, ω-linear aliphatic dicarboxylic acid having 4 to 7 carbon atoms is used as the dicarboxylic acid component, it is preferable to use terephthalic acid or isophthalic acid from the viewpoint of molding processability and barrier property. ..
When a dicarboxylic acid other than α, ω-linear aliphatic dicarboxylic acid having 4 to 7 carbon atoms is used as the dicarboxylic acid component, it is less than 50 mol% and 30 mol% or less of the constituent unit derived from the dicarboxylic acid. Is preferable, more preferably 1 to 25 mol%, and particularly preferably 5 to 20 mol%.

In the xylylene-based polyamide resin used in the present invention, 70 mol% or more of the constituent units derived from the diamine are derived from xylylenediamine, and the xylylenediamine contains 70 mol% or more of the m-xylylenediamine and is derived from the dicarboxylic acid. It is preferable that 70 mol% or more of the constituent units of the above are derived from adipic acid.

Further, the xylylene-based polyamide resin used in the present invention contains lactams such as ε-caprolactam and laurolactam as components constituting the polyamide resin in addition to the diamine component and the dicarboxylic acid component, as long as the effects of the present invention are not impaired. , Aminocaproic acid, aminoundecanoic acid and other aliphatic aminocarboxylic acids can also be used as the copolymerization component. The components other than the diamine component and the dicarboxylic acid component, which may be contained in these xylylene-based polyamide resins, are preferably 5% by mass or less, and more preferably 1% by mass or less of the polyamide resin.

The xylylene-based polyamide resin used in the present invention preferably has a number average molecular weight (Mn) of 6,000 to 30,000, more preferably 8,000 to 28,000, and even more preferably 9,000 to 9000. It is 26,000, more preferably 10,000 to 24,000, and even more preferably 11,000 to 22,000. Within such a range, heat resistance, elastic modulus, dimensional stability, and molding processability become better.

The number average molecular weight (Mn) referred to here is _{the following formula from the terminal amino group concentration [NH 2} ] (μ equivalent / g) and the terminal carboxyl group concentration [COOH] (μ equivalent / g) of the polyamide resin. It is calculated.
Number average molecular weight (Mn) = 2,000,000 / ([COOH] + [NH ₂ ])

The xylylene-based polyamide resin used in the present invention preferably has a molecular weight distribution (weight average molecular weight / number average molecular weight (Mw / Mn)) of 1.8 to 3.1. The molecular weight distribution is more preferably 1.9 to 3.0, still more preferably 2.0 to 2.9. By setting the molecular weight distribution in such a range, it tends to be easy to obtain a molded product having excellent mechanical properties.
The molecular weight distribution of the polyamide resin can be adjusted by appropriately selecting, for example, the type and amount of the initiator and catalyst used at the time of polymerization and the polymerization reaction conditions such as reaction temperature, pressure and time. Further, it can be adjusted by mixing a plurality of types of polyamide resins having different average molecular weights obtained under different polymerization conditions, or by fractionally precipitating the polymerized polyamide resin.

The molecular weight distribution can be obtained by GPC measurement. Specifically, Tosoh's "HLC-8320GPC" is used as a measuring device, and two Tosoh's "TSK gel Super HM-H" are used as columns for elution. A hexafluoroisopropanol (HFIP) solution (concentration: 10 mmol / L) of sodium trifluoroacetate was used as the liquid, the resin concentration was 0.02% by mass, the column temperature was 40 ° C., the flow velocity was 0.3 mL / min, and the refractive index detector (RI). ), And can be obtained as a standard polymethylmethacrylate-converted value. In addition, the calibration curve is prepared by dissolving 6 levels of PMMA in HFIP and measuring.

In the present invention, the melting point of the xylylene-based polyamide resin is preferably 150 to 310 ° C., more preferably 180 to 300 ° C., and even more preferably 190 to 300 ° C.
The glass transition point of the xylylene-based polyamide resin is preferably 50 to 100 ° C.

The melting point in the present invention means the temperature of the peak top of the endothermic peak at the time of temperature rise observed by the DSC (differential scanning calorimetry) method. The glass transition point is a glass transition point that is measured by heating and melting the sample once to eliminate the influence of the thermal history on the crystallinity, and then raising the temperature again.
For these measurements, a DSC measuring device is used, the amount of sample (resin) is about 3 mg, nitrogen is flowed as an atmospheric gas at 30 mL / min, and the temperature rise rate is expected from room temperature under the condition of 10 ° C./min. The melting point can be obtained from the temperature of the peak top of the heat absorption peak observed when the heat is heated to a temperature higher than the melting point and melted. Next, the molten resin is rapidly cooled with dry ice, and the temperature is raised again to a temperature equal to or higher than the melting point at a rate of 10 ° C./min to determine the glass transition point and the melting point. As the DSC measuring instrument, a DSC-60 manufactured by SHIMADZU CORPORATION can be used.

The resin composition of the present invention preferably contains a xylylene-based polyamide resin in a proportion of 20 to 50% by mass of the resin composition. The xylylene-based polyamide resin is preferably contained in a proportion of 22% by mass or more, more preferably 25% by mass or more, and preferably 45% by mass or less, preferably 40. It is more preferably contained in a proportion of mass% or less, and may be 35 mass% or less.

<Polyamide resin 6>
The resin composition of the present invention contains the polyamide resin 6 in a proportion of 5 to 25% by mass of the resin composition. The polyamide resin 6 is preferably contained in a proportion of 8% by mass or more, more preferably 12% by mass or more, further preferably 15% by mass or more, and 22. It is preferably contained in a proportion of mass% or less. Within such a range, the light transmittance of the obtained molded product tends to be remarkably improved.
Polyamide 6 is a ring-opening polymer of ε-caprolactam, but may contain other structural units as long as it does not deviate from the gist of the present invention. Specifically, the diamine component and dicarboxylic acid component described in the above-mentioned xylylene-based polyamide resin, lactams other than ε-caprolactam such as laurolactam, and aliphatic aminocarboxylic acids such as aminocaproic acid and aminoundecanoic acid are copolymerized. Can be used as an ingredient. These copolymerization components are preferably 5% by mass or less, and more preferably 1% by mass or less of the polyamide 6.

<Blend of xylylene-based polyamide resin and polyamide resin 6>
The blend ratio (mass ratio) of the xylylene-based polyamide resin and the polyamide resin 6 is preferably 90 to 50: 10 to 50, more preferably 90 to 52: 10 to 48, and 70 to 52:30 to. It is even more preferably 48, even more preferably 65-54: 35-46, and even more preferably 60-54: 40-46.
The xylylene-based polyamide resin may contain only one type, or may contain two or more types. When two or more kinds are included, the total amount is preferably in the above range.
The resin composition of the present invention may or may not contain a polyamide resin other than the xylylene-based polyamide resin and the polyamide resin 6. In the present invention, it is preferable that the resin composition does not substantially contain a polyamide resin other than the xylylene-based polyamide resin and the polyamide resin 6. The term "substantially free" means that the total amount of the xylylene-based polyamide resin and the polyamide resin other than the polyamide resin 6 is 5% by mass or less of the above-mentioned polyamide resin component (xylylene-based polyamide resin and polyamide resin 6). It is preferably 3% by mass or less, and more preferably 1% by mass or less.

<Other resin components>
The resin composition of the present invention may contain a resin component other than the polyamide resin.
As other resins, polyester resins such as polyethylene terephthalate and polybutylene terephthalate, and thermoplastic resins such as polycarbonate resin and polyacetal resin can be used.
The resin composition of the present invention may be configured so as to substantially not contain a resin component other than the polyamide resin, and is, for example, 5% by mass or less of the total amount of the resin component contained in the resin composition. It can also be 1% by mass or less, particularly 0.4% by mass or less.
That is, the resin composition of the present invention preferably occupies 95% by mass or more of the resin component contained in the resin composition in the total of the xylylene-based polyamide resin and the polyamide resin 6.
In particular, it is preferable that the resin composition of the present invention does not substantially contain an impact resistance improving agent. The term "substantially free" means that the blending amount of the polyamide resin 6 is 5% by mass or less, and further, it may be 1% by mass or less, particularly 0.4% by mass or less.

<Glass fiber>
The resin composition of the present invention contains glass fibers.
The glass fiber has a glass composition such as A glass, C glass, E glass, and S glass, and E glass (non-alkali glass) is particularly preferable.

The glass fiber used in the resin composition of the present invention may be a single fiber or a plurality of single fibers twisted together.
The form of glass fiber is "glass roving", which is a continuous winding of single fiber or multiple twisted fibers, "chopped strand", which has a cut length (number average fiber length) of 1 to 10 mm, and crushed length (crushed length). It may be any of "milled fibers" having a number average fiber length of 10 to 500 μm. Such glass fibers are commercially available from Asahi Fiber Glass Co., Ltd. under the trade names of "Glaslon chopped strand" and "Glaslon milled fiber" and are easily available. As the glass fiber, those having different morphologies can be used in combination.

Further, in the present invention, glass fibers having an irregular cross-sectional shape are also preferable. The irregular cross-sectional shape is defined as, for example, 1. It is 5 to 10, and more preferably 2.5 to 10, more preferably 2.5 to 8, and particularly preferably 2.5 to 5. Regarding such flat glass, the description in paragraphs 0065 to 0072 of JP2011-195820A can be referred to, and the contents thereof are incorporated in the present specification.

The glass fiber in the present invention may be glass beads. The glass beads are spherical beads having an outer diameter of 10 to 100 μm, and are commercially available, for example, from Potters Barotini under the trade name “EGB731” and are easily available. Further, the glass flakes are scaly flakes having a thickness of 1 to 20 μm and a side length of 0.05 to 1 mm. For example, they are commercially available from Nippon Sheet Glass Co., Ltd. under the trade name of “Freka”. , Easily available.

The glass fiber used in the present invention is particularly preferably a glass fiber having a weight average fiber diameter of 1 to 20 μm and a cut length (number average fiber length) of 1 to 10 mm. Here, when the cross section of the glass fiber is flat, the weight average fiber diameter is calculated as the weight average fiber diameter in a circle having the same area.
The glass fiber used in the present invention may be focused with a sizing agent. As the sizing agent in this case, a urethane-based sizing agent is preferable.

The content of the glass fiber in the resin composition of the present invention is 25% by mass or more, preferably 35% by mass or more, and may be 40% by mass or more in the resin composition. Further, the content of the glass fiber in the resin composition of the present invention is 60% by mass or less, preferably 55% by mass or less in the resin composition.
The resin composition of the present invention may contain only one type of glass fiber, or may contain two or more types of glass fibers. When two or more kinds are included, the total amount is preferably in the above range.

In the resin composition of the present invention, the mass ratio of the polyamide resin 6 to the glass fiber is preferably 1: 2.0 to 6.0. With such a ratio, the effect of the present invention is more effectively exhibited.

<Light transmissive dye>
The light-transmitting dye used in the present invention is usually a black dye, specifically, niglosin, naphthalocyanine, aniline black, phthalocyanine, porphyrin, perinone, perylene, quaterylene, azo dye, anthraquinone, squaric acid derivative, and Examples include immonium dyes.
Examples of commercially available products include e-BIND LTW-8731H and e-BIND LTW-8701H, which are colorants manufactured by Orient Chemical Industry Co., Ltd.
The content of the light-transmitting dye in the resin composition of the present invention is preferably 0.001 part by mass or more, more preferably 0.005 part by mass or more, based on 100 parts by mass of the polyamide resin component. It is more preferably 0.01 part by mass or more, further preferably 0.03 part by mass or more, and may be 0.04 part by mass or more. The upper limit of the content of the light-transmitting dye is preferably 5 parts by mass or less, more preferably 4 parts by mass or less, and 1 part by mass or less with respect to 100 parts by mass of the polyamide resin component. More preferably, it may be 0.2 parts by mass or less, 0.1 parts by mass or less, and 0.06 parts by mass or less. The light-transmitting dye may contain only one type, or may contain two or more types. When two or more kinds are included, the total amount is preferably in the above range.
Further, it is preferable that the resin composition of the present invention does not substantially contain carbon black. The term "substantially free" means, for example, 0.0001% by mass or less of the resin composition.

<Talc>
The resin composition of the present invention may contain talc. In the present invention, crystallization can be promoted by blending talc.
The content of talc in the resin composition of the present invention is preferably 0.05 to 20% by mass, more preferably 0.1 to 10% by mass, and 0.15 with respect to the resin composition. It is more preferably ~ 5% by mass, and particularly preferably 0.2 to 1.0% by mass. Only one type of talc may be used, or two or more types may be used in combination. In the case of two or more types, the total amount is preferably in the above range.
In the resin composition of the present invention, the mass ratio of the light-transmitting dye and talc is preferably 10 to 3: 1, more preferably 8 to 4: 1, and 8 to 5: 1. Is even more preferable. With such a ratio, the effect of the present invention is more effectively exhibited.

<Release agent>
The resin composition of the present invention may further contain a mold release agent. The release agent is mainly used to improve the productivity of the resin composition during molding. Examples of the release agent include aliphatic carboxylic acid amides, aliphatic carboxylic acids, esters of aliphatic carboxylic acids and alcohols, aliphatic hydrocarbon compounds having a number average molecular weight of 200 to 15,000, and polysiloxane-based silicone oils. Can be mentioned. Among these release agents, carboxylic acid amide compounds are particularly preferable.

Examples of the aliphatic carboxylic acid amide system include compounds obtained by a dehydration reaction between a higher aliphatic monocarboxylic acid and / or a polybasic acid and a diamine.
For details of the release agent, the description of paragraphs 0037 to 0042 of JP2016-196563 and the description of paragraphs 0048 to 0058 of JP2016-078318 can be referred to, and these contents are incorporated in the present specification. ..

When blended, the lower limit of the release agent content is preferably 0.001% by mass or more, more preferably 0.01% by mass or more, and the upper limit value with respect to the resin composition. Is preferably 2% by mass or less, more preferably 1.5% by mass or less. Within such a range, the mold releasability can be improved, and mold contamination during injection molding can be prevented. As the release agent, one type may be used alone or two or more types may be used in combination. When two or more types are used, the total amount is preferably in the above range.

<Other ingredients>
The resin composition of the present invention may contain other components as long as the gist of the present invention is not deviated. Such additives include fillers other than glass fiber, light stabilizers, antioxidants, flame retardants, UV absorbers, optical brighteners, dripping inhibitors, antistatic agents, antifogging agents, lubricants, and antiblocking agents. Examples include agents, fluidity improvers, plasticizers, dispersants, antibacterial agents and the like. Only one of these components may be used, or two or more of these components may be used in combination.
In the resin composition of the present invention, the contents of the resin component, the light-transmitting dye, the glass fiber and other additives are adjusted so that the total of each component is 100% by mass.

The resin composition of the present invention preferably has a light transmittance of 16% or more at a wavelength of 800 nm according to ISO 13468-1 and ISO 13468-2 when molded into a test piece having a thickness of 3.0 mm. % Or more, more preferably 20% or more, and even more preferably 22% or more. The upper limit of the light transmittance is not particularly defined, but for example, 45% or less, 40% or less, and 30% or less are sufficiently practical levels. The light transmittance is measured by the method described in Examples described later.
The resin composition of the present invention also preferably has a light transmittance of 17% or more at a wavelength of 1000 nm according to ISO 13468-1 and ISO 13468-2 when molded into a test piece having a thickness of 3.0 mm. , 20% or more, more preferably 23% or more, and even more preferably 25% or more. The upper limit of the light transmittance is not particularly defined, but for example, 45% or less, 40% or less, and 30% or less are sufficiently practical levels. The light transmittance is measured by the method described in Examples described later.

The resin composition of the present invention preferably has an L value of 5.0 or less, more preferably 4.5 or less, and 4.3 or less when molded into a test piece having a thickness of 2 mm. Is even more preferable. The lower limit of the L value is preferably 3.5 or more.

<Manufacturing method of resin composition>
The method for producing the resin composition of the present invention is not particularly limited, but a method of using a single-screw or twin-screw extruder having equipment capable of devolatile from the vent port as a kneader is preferable. The above-mentioned polyamide resin component, glass fiber and other additives to be blended as needed may be supplied to the kneader all at once, or other blending components may be sequentially supplied to the polyamide resin component. The glass fiber is preferably supplied from the middle of the extruder in order to prevent crushing during kneading. Further, two or more kinds of components selected from each component may be mixed and kneaded in advance.
In the present invention, the light-transmitting dye can be prepared in advance by master-batching with a polyamide resin or the like and kneaded with the xylylene-based polyamide resin and the polyamide resin 6 to obtain the resin composition of the present invention.

The method for producing a molded product using the resin composition of the present invention is not particularly limited, and is a molding method generally used for thermoplastic resins, that is, a molding method such as injection molding, hollow molding, extrusion molding, or press molding. Can be applied. In this case, a particularly preferable molding method is injection molding because of its good fluidity. In injection molding, it is preferable to control the resin temperature to 250 to 300 ° C.

<Kit>
The present invention also discloses a kit having the above resin composition and a light absorbing resin composition containing a thermoplastic resin and a light absorbing dye. The kit of the present invention is preferably used for producing a molded product by laser welding.
That is, the resin composition contained in the kit serves as a light-transmitting resin composition, and the molded product obtained by molding the light-transmitting resin composition is a transparent resin member for laser light during laser welding. Become. On the other hand, a molded product obtained by molding a light-absorbing resin composition is an absorbing resin member for laser light during laser welding.

<< Light Absorbent Resin Composition >>
The light-absorbing resin composition used in the present invention contains a thermoplastic resin and a light-absorbing dye, and may further contain an inorganic filler.
Examples of the thermoplastic resin include polyamide resin, olefin resin, vinyl resin, styrene resin, acrylic resin, polyphenylene ether resin, polyester resin, polycarbonate resin, and polyacetal resin, which have good compatibility with the resin composition. From this point of view, a polyamide resin, a polyester resin, and a polycarbonate resin are particularly preferable, and a polyamide resin is more preferable. Further, the thermoplastic resin may be of one kind or two or more kinds.
The type of the polyamide resin used in the light-absorbing resin composition is not defined, and the above-mentioned polyamide resin (xylylene-based polyamide resin or polyamide resin 6 and a mixture thereof) may or may not be used. You may.
Examples of the inorganic filler include fillers capable of absorbing laser light such as glass fiber, carbon fiber, silica, alumina, talc, carbon black, and an inorganic powder coated with a material that absorbs laser, and glass fiber is preferable. The glass fiber has the same meaning as the glass fiber that may be blended in the resin composition of the present invention, and the preferable range is also the same.
The light-absorbing dye has a maximum absorption wavelength in the range of the laser light wavelength to be irradiated, that is, in the present invention, in the range of 800 nm to 1100 nm, and is an inorganic pigment (carbon black (for example, acetylene black, lamp black)). , Thermal black, furnace black, channel black, Ketjen black, etc.), red pigments such as iron oxide red, orange pigments such as molybdate orange, white pigments such as titanium oxide), organic pigments (yellow pigments, Orange pigments, red pigments, blue pigments, green pigments, etc.) and the like. Among them, the inorganic pigment generally has a strong hiding power and is preferable, and the black pigment is more preferable. Two or more of these light-absorbing dyes may be used in combination. The content of the light-absorbing dye is preferably 0.01 to 30 parts by mass with respect to 100 parts by mass of the resin component.

<< Laser Welding Method >>
Next, the laser welding method will be described. In the present invention, a molded product (transmissive resin member) obtained by molding the resin composition of the present invention and a molded product (absorbent resin member) obtained by molding the light-absorbing resin composition are molded by laser welding. Goods can be manufactured. By laser welding, the transmissive resin member and the absorbent resin member can be firmly welded without using an adhesive.
The shape of the members is not particularly limited, but since the members are used by joining them by laser welding, they usually have at least surface contact points (plane, curved surface). In laser welding, the laser light transmitted through the transmitting resin member is absorbed by the absorbing resin member and melted, and both members are welded. Although the molded product of the resin composition of the present invention contains glass fibers, it has high transparency to laser light, and therefore can be preferably used as a transmissive resin member. Here, the thickness of the member through which the laser light is transmitted (the thickness in the laser transmission direction in the portion through which the laser light is transmitted) can be appropriately determined in consideration of the application, the composition of the resin composition, and the like, and is, for example, 5 mm or less. It is preferably 4 mm or less.

The laser light source used for laser welding can be determined according to the light absorption wavelength of the light-absorbing dye, and a laser having a wavelength in the range of 800 to 1100 nm is preferable, and for example, a semiconductor laser or a fiber laser can be used.

More specifically, for example, when welding a transparent resin member and an absorbing resin member, first, the welded portions of both are brought into contact with each other. At this time, it is desirable that the welding points of both are in surface contact, and may be a combination of flat surfaces, curved surfaces, or a flat surface and a curved surface. Next, the laser beam is irradiated from the transmission resin member side. At this time, if necessary, a lens may be used to condense the laser light on the interface between the two. The focused beam transmits through the transmitting resin member, is absorbed near the surface of the absorbing resin member, generates heat, and melts. Next, the heat is transferred to the transmissive resin member by heat conduction and melted, a molten pool is formed at the interface between the two, and after cooling, the two are joined.
The molded product in which the transparent resin member and the absorbent resin member are welded in this way has high bonding strength. The molded product in the present invention is intended to include not only finished products and parts but also members forming a part thereof.

The molded product obtained by laser welding in the present invention has good mechanical strength, high welding strength, and less damage to the resin due to laser light irradiation. -Applicable to electronic equipment parts, office automation (OA) equipment parts, home appliance equipment parts, machine mechanism parts, vehicle mechanism parts, etc. In particular, food containers, chemical containers, oil and fat product containers, hollow parts for vehicles (various tanks, intake manifold parts, camera housings, etc.), electrical parts for vehicles (various control units, ignition coil parts, etc.), motor parts, It can be suitably used for various sensor parts, connector parts, switch parts, breaker parts, relay parts, coil parts, transformer parts, lamp parts and the like. In particular, the resin compositions and kits of the present invention are suitable for in-vehicle camera modules.

Hereinafter, the present invention will be described in more detail with reference to examples. The materials, amounts used, ratios, treatment contents, treatment procedures, etc. shown in the following examples can be appropriately changed as long as they do not deviate from the gist of the present invention. Therefore, the scope of the present invention is not limited to the specific examples shown below.

Raw material <Polyamide resin>
Xylylene-based polyamide resin (MXD6): Polymethaxylylene adipamide, manufactured by Mitsubishi Gas Chemical Company, MX nylon S6001
Polyamide resin 6: UBE Nylon 1011FB manufactured by Ube Industries, Ltd.
Polyamide resin 610: Toray Industries, Inc., Amiran CM2001

<Glass fiber>
T756H: manufactured by Nippon Electric Glass Co., Ltd., ECS03T-756H, weight average fiber diameter 10.5 μm, cut length 3 mm

<Talc>
Micron White # 5000S: Made by Hayashi Kasei Co., Ltd.

<Release agent>
CS8CP: Made by Nitto Kasei Kogyo Co., Ltd.

<Light transmissive dye>
LTD-8701H: Masterbatch of e-BIND LTD LTW-8701H, polyamide 66 and light-transmitting dye manufactured by Orient Chemical Industry Co., Ltd.

<Example 1>
<< Compound >>
The polyamide resin component, talc, mold release agent, and light-transmitting dye are weighed and dry-blended so as to have the composition shown in Table 1 below (each component in Table 1 is expressed in% by mass). It was introduced from the screw root of a twin-screw extruder (manufactured by Toshiba Machine Co., Ltd., TEM26SS) using a twin-screw screw type cassette waving feeder (manufactured by Kubota, CE-W-1-MP). Further, the glass fiber is put into the above-mentioned twin-screw extruder from the side of the extruder using a vibrating cassette waving feeder (CE-V-1B-MP manufactured by Kubota), and melt-kneaded with the resin component and the like. , Resin composition pellets were obtained. The temperature setting of the extruder was 280 ° C.

<< Bending strength and flexural modulus >>
The resin pellets obtained by the above-mentioned production method were dried at 120 ° C. for 4 hours, and then an ISO tensile test piece having a thickness of 4 mm was injection-molded using NEX140III manufactured by Nissei Resin Industry Co., Ltd. The molding was carried out at a cylinder temperature of 280 ° C. and a mold surface temperature of 130 ° C.
In accordance with ISO178, the flexural strength (unit: MPa) and flexural modulus (unit: GPa) were measured at a temperature of 23 ° C. using the ISO tensile test piece (4 mm thickness).

<< Displacement of fracture point >>
A bending test according to the ISO178 standard was performed using a fully automatic bending test system (model B-2) manufactured by Toyo Seiki Seisakusho Co., Ltd., and the fracture point displacement (unit: mm) of the test piece was measured.

<< Light Transmittance >>
The light transmittance was measured according to ISO 13468-1 and ISO 13468-2. Specifically, the resin composition pellets obtained above are dried at 120 ° C. for 4 hours, and then used for light transmittance measurement using an injection molding machine (SE-50D, manufactured by Sumitomo Heavy Industries, Ltd.). A test piece (3.0 mm thick) was prepared. The light transmittance was measured using a visible / ultraviolet spectrophotometer (UV-3100PC, manufactured by Shimadzu Corporation), and the light transmittance (unit:%) at wavelengths of 1000 nm and 800 nm was measured, respectively.

<< Charpy Impact Strength >>
Using the ISO tensile test piece obtained by the above method, the notched Charpy impact strength was measured under the conditions of 23 ° C. in accordance with ISO179-1 and ISO179-2. The unit of Charpy impact strength is kJ / m ² .

<< L value of resin composition >>
Using a color difference meter SpectroPhotometer SE6000 manufactured by Nippon Denshoku Industries Co., Ltd., a 2 mm thick portion of a test piece for measuring light transmittance obtained by the above method was measured by a transmission method with a C light source and a field of view of 2 °.

Example 2, Comparative Examples 1 to 3
In Example 1 above, the changes were made as shown in Table 1, and the others were carried out in the same manner.

As is clear from the above results, in the composition containing MXD6, the glass fiber, and the light-transmitting dye, when the polyamide resin 6 is blended (Examples 1 and 2), when the polyamide resin 6 is not blended (Comparative Example 1), or Compared with the case where other aliphatic polyamide resins were blended (Comparative Examples 2 and 3), high light transmittance could be achieved while improving toughness.
It is extremely surprising that the light transmittance is remarkably improved by blending the polyamide resin 6.

Claims (11)

It is composed of a diamine-derived structural unit and a dicarboxylic acid-derived structural unit. 70 mol% or more of the diamine-derived structural unit is derived from xylylene diamine, and 70 mol% or more of the dicarboxylic acid-derived structural unit has carbon number. A xylylene-based polyamide resin derived from 4 to 7 α, ω-linear aliphatic dicarboxylic acid,
Polyamide resin 6 and
With glass fiber
A laser welding resin composition containing a light-transmitting dye.
The polyamide resin 6 is included in a proportion of 5 to 25 wt% of the laser weldable resin composition,
The glass fibers, including Murrell, laser weldable resin composition at a ratio of 25 to 60 wt% of the laser weldable resin composition. The laser L value of welding the resin composition is 5.0 or less, laser weldable resin composition according to claim 1. The laser welding resin composition according to claim 1 or 2, wherein the total of the xylylene-based polyamide resin and the polyamide resin 6 accounts for 95% by mass or more of the resin component contained in the laser welding resin composition. The laser welding resin composition according to any one of claims 1 to 3, wherein the glass fiber is contained in a proportion of 35 to 55% by mass of the laser welding resin composition. The laser welding resin composition according to any one of claims 1 to 4, wherein the xylylenediamine contains metaxylylenediamine. The laser welding resin composition according to any one of claims 1 to 5, wherein 70 mol% or more of the constituent unit derived from the dicarboxylic acid is derived from adipic acid. It is composed of a diamine-derived structural unit and a dicarboxylic acid-derived structural unit. A laser-welded resin composition containing an acid-derived xylylene-based polyamide resin, a polyamide resin 6, glass fibers, and a light-transmitting dye. The polyamide resin 6 is a laser-welded resin composition 12 25 wt% proportion in included in the glass fibers, including Murrell in a proportion of 35 to 55 wt% of the laser weldable resin composition, for laser welding according to claim 1 Resin composition. The laser welding resin composition according to any one of claims 1 to 7, further comprising talc. A kit comprising the laser welding resin composition according to any one of claims 1 to 8 and a light absorbing resin composition containing a thermoplastic resin and a light absorbing dye. A molded product obtained by molding the laser-welded resin composition according to any one of claims 1 to 8, and a light-absorbing resin composition containing a thermoplastic resin and a light-absorbing dye. A method for producing a molded product, which comprises laser welding the molded product. A molded product obtained by molding the laser welding resin composition according to any one of claims 1 to 8 or the kit according to claim 9.