JP3474246B2 - Base resin composition for electronic parts - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a novel polyamide-based base resin composition for electronic parts. More specifically, the present invention relates to a polyamide resin composition having excellent solder heat resistance as well as excellent performances such as mechanical strength, toughness, impact resistance, low water absorption, and chemical resistance. It can be used preferably.

[0002]

2. Description of the Related Art Conventionally, as a method of mounting an electronic component on a printed wiring board, a lead-through method, that is, a lead hole is formed in a substrate, and a lead of the component is passed through the lead hole to form a lead and a land on the substrate on the opposite side. The technique of soldering was used. However, at present, the surface mount method (SMT) is advantageous for high density, miniaturization of parts, and cost reduction.
Is rapidly penetrating. (However, as the mounting form of the electronic device, the most suitable component considering the cost performance from the performance / price is used. Therefore, it is not yet possible to assemble the circuit board entirely with surface mount components (SMD). Not many, conventional lead-through components and SMD
In many cases, the circuit board is assembled together with. )

In SMT, a soldering method such as a flow method or a reflow method is used, and in either case, high heat resistance to withstand a solder melting temperature is required. Resins that have been conventionally used in this field include PPS and nylon 4
6 and the like. However, in the former case, there are problems such as gas generation during molding, burrs and mechanical performance, and in the latter case such as dimensional change due to water absorption and occurrence of water swelling during reflow. On the other hand, recently, a so-called 6T-based polyamide obtained by copolymerizing a polyamide composed of hexamethylenediamine and terephthalic acid with a tens% of a third component has entered the field, and is disclosed in JP-A-3-88846 and JP-A-3-72565. Japanese Unexamined Patent Publications and the like also disclose that semi-aromatic polyamides such as 6T-based polyamides can be used as electronic parts for infrared reflow.

In the soldering method of SMT, infrared reflow is shifting to air reflow, and the heat resistance required as a whole tends to decrease, but on the other hand, there is a strong demand for solder heat resistance higher than conventional. From the standpoint of reliability as well, there is an increasing expectation for a resin having improved heat resistance and well-balanced moldability and mechanical performance.

[0005]

SUMMARY OF THE INVENTION Electronic components, especially SMD
When used as, the conventional PPS and nylon 46 have the above-mentioned disadvantages.
According to the studies made by the present inventors, the T-based polyamide is not always a resin that is sufficiently satisfactory in terms of heat resistance, water absorption, toughness, and the like.

An object of the present invention is as a resin for electronic parts,
It is an object of the present invention to provide a polyamide composition having excellent solder heat resistance and excellent performances such as low water absorption, toughness and chemical resistance.

[0007]

Means for Solving the Problems As a result of intensive studies for solving the above problems, the inventors of the present invention are the first to use a polyamide containing terephthalic acid and 1,9-nonanediamine as main components for the first time. The inventors have found that a resin for electronic parts having excellent performance can be obtained, and have completed the present invention.

According to the present invention, the above object is to provide a dicarboxylic acid component in which 60 to 100 mol% of the dicarboxylic acid component is terephthalic acid and 60 to 100 mol% of the diamine component.
Of 1,9-nonanediamine is a diamine component, and [η] measured at 30 ° C. in concentrated sulfuric acid is 0.4 to 3.0.
dl / g der is, more than 70% of the terminal groups is achieved by providing an electronic component-based resin composition comprising <br/> polyamides are sealed.

The present invention will be specifically described below. The polyamide serving as the base resin of the resin composition for electronic parts of the present invention has a terephthalic acid component of 60 mol% or more, preferably 75 mol% or more, more preferably 90 mol% or more, of the dicarboxylic acid components used. Is. When the content of the terephthalic acid component is less than 60 mol%, various properties such as solder heat resistance and chemical resistance of the obtained polyamide are deteriorated, which is not preferable.

Other dicarboxylic acid components other than the terephthalic acid component include malonic acid, dimethylmalonic acid, succinic acid, glutaric acid, adipic acid, 2-methyladipic acid,
Aliphatic dicarboxylic acids such as trimethyladipic acid, pimelic acid, 2,2-dimethylglutaric acid, 3,3-diethylsuccinic acid, azelaic acid, sebacic acid, suberic acid; 1,3-cyclopentanedicarboxylic acid, 1,4 An alicyclic dicarboxylic acid such as cyclohexanedicarboxylic acid;
Isophthalic acid, 2,6-naphthalenedicarboxylic acid, 2,
7-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,4-phenylenedioxydiacetic acid, 1,3
-Phenylenedioxydiacetic acid, diphenic acid, dibenzoic acid, 4,4'-oxydibenzoic acid, diphenylmethane-
4,4'-dicarboxylic acid, diphenyl sulfone-4,
Aromatic dicarboxylic acids such as 4'-dicarboxylic acid and 4,4'-biphenyldicarboxylic acid, or any mixture thereof can be mentioned. Of these, aromatic dicarboxylic acids are preferably used. Further, polyvalent carboxylic acids such as trimellitic acid, trimesic acid and pyromellitic acid can be used within the range where melt molding is possible.

As the diamine component used in the polyamide which is the base resin of the resin composition for electronic parts of the present invention, the 1,9-nonanediamine component is 60 mol% or more, preferably 75 mol% or more, more preferably It is 90 mol% or more.

As diamine components other than the 1,9-nonanediamine component, ethylenediamine, propylenediamine, 1,4-butanediamine, 1,6-hexanediamine, 1,8-octanediamine, 1,10-decanediamine. , 1,12-dodecanediamine, 3-methyl-
1,5-pentanediamine, 2,2,4-trimethyl-
1,6-hexanediamine, 2,4,4-trimethyl-
Aliphatic diamines such as 1,6-hexanediamine, 2-methyl-1,8-octanediamine, 5-methyl-1,9-nonanediamine; alicyclic diamines such as cyclohexanediamine, methylcyclohexanediamine and isophoronediamine; p -Aromatic diamines such as phenylenediamine, m-phenylenediamine, xylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylsulfone and 4,4'-diaminodiphenylether, or any mixture thereof. be able to. Among them, 2-methyl-1,8-octanediamine is preferable.

[0013] Polyamides as a base resin of an electronic component resin composition of the present invention, more than 70% of the terminal groups of the molecular chain, such as monocarboxylic acids and monoamines, reacting with an amino group or carboxyl group of the polyamide terminus It is necessary that the compound is sealed with an end-capping agent that is a monofunctional compound having properties . By performing end-capping, a composition having further excellent properties such as melt stability and hot water resistance can be obtained.

The amount of the end-capping agent used when producing the base resin polyamide of the resin composition for electronic parts of the present invention is determined by the reactivity, boiling point, reaction apparatus, reaction conditions, etc. of the end-capping agent used. Depending on the total number of moles of dicarboxylic acid and diamine, 0.1 to 15 mol%
Used within the range of.

The polyamide as the base resin of the resin composition for electronic parts of the present invention can be produced by any method known as a method for producing a crystalline polyamide. For example, the polymerization can be carried out by a solution polymerization method using an acid chloride and a diamine as raw materials or an interfacial polymerization method, a melt polymerization method using a dicarboxylic acid and a diamine as raw materials, a solid phase polymerization method, a melt extruder polymerization method and the like. Below, an example of the polymerization method of polyamide is shown.

According to the research conducted by the present inventors, a catalyst and, if necessary, an end-capping agent were first added to a diamine and a dicarboxylic acid all at once, to prepare a nylon salt, and then once at 200 to 250 ° C. 30 ℃ in concentrated sulfuric acid at the temperature of
Viscosity [η] at 0.15 to 0.25 dl / g
The polyamide of the present invention can be easily obtained by subjecting the prepolymer of (1) to solid phase polymerization or performing polymerization using a melt extruder. When the intrinsic viscosity [η] of the prepolymer is within the range of 0.15 to 0.25 dl / g, the deviation of the molar balance between the carboxyl group and the amino group and the decrease in the polymerization rate are small in the post-polymerization stage, and the molecular weight is further reduced. A polyamide with a small distribution and excellent performance and moldability can be obtained. When the final stage of the polymerization is carried out by solid phase polymerization, it is preferably carried out under reduced pressure or under the flow of an inert gas, and if the polymerization temperature is in the range of 200 to 250 ° C., the polymerization rate is large and the productivity is excellent. It is preferable because coloring and gelation can be effectively suppressed. When the final stage of polymerization is carried out by a melt extruder, the polymerization temperature is 370 ° C.
It is preferable for it to be less than that the polyamide is hardly decomposed and a polyamide without deterioration can be obtained.

The [η] of the polyamide used in the composition of the present invention measured in concentrated sulfuric acid at 30 ° C. is 0.4 to 3.0.
dl / g, preferably 0.6 to 2.0 dl / g,
More preferably, it is 0.8 to 1.8 dl / g. [Η]
Is preferably in this range because the polymer obtained has good mechanical performance and moldability.

In the production of the above polyamide, in addition to the above-mentioned terminal blocking agent, for example, as a catalyst, phosphoric acid, phosphorous acid, hypophosphorous acid or a salt or ester thereof,
Specifically, potassium, sodium, magnesium, vanadium, calcium, zinc, cobalt, manganese, tin,
Metal salts such as tungsten, germanium, titanium and antimony, ammonium salts, ethyl ester, isopropyl ester, butyl ester, hexyl ester, isodecyl ester, octadecyl ester, decyl ester, stearyl ester, phenyl ester and the like can be added.

The polyamide composition of the resin composition for electronic parts of the present invention preferably contains a crystal nucleating agent as an additive. As the crystal nucleating agent, zinc oxide, magnesium oxide, iron oxide, antimony oxide, titanium oxide, alumina,
Inorganic salts such as metal oxides such as silica, sodium carbonate, potassium carbonate, calcium carbonate, zinc carbonate, magnesium carbonate, calcium silicate, lead silicate, magnesium silicate, calcium phosphate, lead phosphate, calcium sulfate, barium sulfate, etc. Talc, kaolin, mica, clay such as acid clay, calcium oxalate, calcium benzoate,
Organic acid salts such as magnesium stearate and zinc salicylate, high melting point polymers such as nylon 6T and nylon 22, zinc powder, aluminum powder, graphite powder, powder simple substance such as carbon black, pt-butylaluminum benzoate, phosphoric acid Bis (4-t-butylphenyl)
Sodium, 2,2'-methylenebis (4,6-di-t-butylphenyl) sodium phosphate, di (pt-butylbenzoic acid) hydroxyaluminum, etc. can be used alone or in combination of two or more. . When using these substances as crystal nucleating agents,
The total amount of the crystal nucleating agent used is preferably 0.01 to 2 parts by weight, more preferably 0.02 to 1 part by weight, based on 100 parts by weight of the polyamide. When the amount added is in this range, it is possible to effectively suppress deformation such as warpage in the soldering step without adversely affecting the mechanical strength and electrical conductivity of the obtained polyamide composition, and the thermal deformation temperature, Performances such as surface beauty, chemical resistance, and low water absorption can be further improved.

The base resin composition for electronic parts of the present invention is
It is also possible to use it as a reinforcing system in which glass fiber, carbon fiber, inorganic powder filler, organic powder filler, etc. are blended.

In addition, the base resin composition for electronic parts of the present invention impairs the above-mentioned characteristics by incorporating a conventionally used flame retardant, that is, a brominated polymer, antimony oxide, metal hydroxide and the like. It is also possible to make flame-retardant without using.

Further, the base resin composition for electronic parts of the present invention contains, in addition to the above additives, a hindered phenol antioxidant, a hindered amine antioxidant system, a phosphorus antioxidant, if necessary. Thio type antioxidant, colorant, ultraviolet absorber, light stabilizer, antistatic agent, plasticizer,
Lubricants or other polymers can also be added.

Examples of the method of compounding the above-mentioned respective components include a method of adding at the time of polycondensation reaction or a method of dry blending, a method of melt kneading and compounding using an extruder, and the like.

As described above, the polyamide composition of the present invention is a very excellent resin when used as an electronic component requiring soldering heat resistance. Specific examples of usage include connectors, switches, IC and LED housings, sockets, relays, resistors, capacitors, coil bobbins, and the like.

[0025]

EXAMPLES Hereinafter, the base resin composition for electronic parts of the present invention will be specifically described by way of examples, but the present invention is not limited thereto. The terminal sealing rate, intrinsic viscosity, tensile strength, tensile elongation, flexural modulus, hot water resistance, chemical resistance, water absorption rate, solder heat resistance, and heat distortion temperature in the examples were measured by the following methods.

End capping ratio: ¹ H-NMR (500 MH
z, measured in deuterated trifluoroacetic acid at 50 ° C.) to measure the number of carboxyl group end, amino group end and capped end respectively from the integrated value of the characteristic signal for each end group, The terminal sealing rate was calculated from (1). The chemical shift values of typical signals used for measurement are shown below. Sealing rate (%) = [(A−B) ÷ A] × 100 (1) [In the formula, A is the total number of end groups of molecular chain (this is usually equal to twice the number of polyamide molecules). And B represents the total number of carboxyl group terminals and amino group terminals.]

[0027]

[Table 1]

Intrinsic viscosity [η]: in concentrated sulfuric acid at 30 ° C.
The intrinsic viscosity (ηinh) of the samples having the concentrations of 0.05, 0.1, 0.2 and 0.4 g / dl was measured, and the value obtained by extrapolating this to the concentration of 0 was defined as the intrinsic viscosity [η]. ηinh = [ln (t ₁ / t ₀ )] / c [wherein, ηinh represents an intrinsic viscosity (dl / g), t ₀ represents a solvent flowing time (second), and t ₁ represents a sample solution flowing down. Time (second), c is the concentration of the sample in the solution (g / dl)
Represents ]

Tensile Strength, Tensile Elongation, Flexural Modulus, Heat Deformation Temperature, Impact Strength: An absolutely dried sample piece injection-molded at a temperature about 20 ° C. higher than the melting point of polyamide was measured by the following method.

[0030]

[Table 2]

Hot water resistance: about 20 ° C. from the melting point of polyamide
A sample piece, which was hot-pressed at a high temperature and punched out with a film having a thickness of 200 microns using JIS No. 3 dumbbells, was heated to 80 ° C.
The sample was immersed in hot water for 10 minutes and the retention of tensile strength of the sample before treatment was measured.

Chemical resistance: about 20 ° C. above the melting point of polyamide
A sample of 200-micron-thick film, which was hot pressed at a high temperature, was punched with JIS No. 3 dumbbells to obtain a sample at 23 ° C.
The sample was dipped in each of the above chemicals for 7 days, and the retention rate of the tensile strength of the sample before treatment was measured.

Water absorption: hot pressed at a temperature 20 ° C. higher than the melting point of polyamide and cooled at 150 ° C. for 5 minutes,
A film (5 cm × 5 cm) having a thickness of about 200 μm was dried under reduced pressure at 120 ° C. for 5 days, weighed, and then dipped in water at 23 ° C. for 10 days, weighed, and added to the weight before dipping for an increase amount. It was calculated as a ratio (%).

Reference Example 1 3272.9 g (19.70 mol) of terephthalic acid,
3165.8 g (20.0 mo) of 1,9-nonanediamine
1), benzoic acid 73.27 g (0.60 mol), and sodium hypophosphite monohydrate 6.5 g (0.
1% by weight) and 6 liters of distilled water were placed in an autoclave having an internal volume of 20 liters and purged with nitrogen. The mixture was stirred at 100 ° C for 30 minutes, and the internal temperature was raised to 210 ° C over 2 hours. At this time, the pressure in the autoclave was increased to 22 kg / cm ² . After continuing the reaction for 1 hour, 230 ℃
The temperature to 230 ° C for 2 hours,
The reaction was carried out while gradually removing the steam to maintain the pressure at 22 kg / cm ² . Next, the pressure is 10 kg / c over 30 minutes.
Lower to m ² and react for 1 hour to obtain an intrinsic viscosity [η]
= 0.25 dl / g of prepolymer was obtained. This one
It was dried under reduced pressure at 00 ° C. for 12 hours and pulverized to a size of 2 mm or less. This is 230 ℃, under 0.1mmHg, 10
Solid-state polymerization for time, melting point 317 ° C, intrinsic viscosity [η] 1.3
A white polyamide having 5 dl / g and a terminal sealing rate of 90% was obtained.

Reference Examples 2-5 Using the dicarboxylic acid component and the diamine component shown in Table 3, a polyamide was produced by the method described in Reference Example 1.

Examples 1 to 5 and Comparative Examples 1 and 2 Polyamides alone or using a twin-screw extruder to prepare the above-mentioned test pieces from compositions containing additives at a temperature about 20 ° C. higher than the melting point of polyamide. Then, the above various performances were evaluated. The results are shown in Table 3.

[0037]

[Table 3]

Comparative Examples 3 and 46 6T type nylon (AMODEL A-10 manufactured by Amoco)
Table 4 shows the performance of the test pieces produced by using (00) 46 nylon (F5000 made by Unitika).

[0039]

[Table 4]

[0040]

EFFECTS OF THE INVENTION The base resin composition for electronic parts of the present invention has excellent solder heat resistance as an electronic part resin, and also has excellent properties such as low water absorption, toughness and chemical resistance.

Continuation of the front page (56) Reference JP-A-3-72565 (JP, A) JP-A-3-88846 (JP, A) JP-A-62-36459 (JP, A) (58) Fields investigated (Int .Cl. ⁷ , DB name) C08L 77/00-77/12 C08G 69/26-69/36 C08K 3/00

Claims (2)

(57) [Claims] 1. 60 to 100 mol% of the dicarboxylic acid component
Is a terephthalic acid component and a diamine component in which 60 to 100 mol% of the diamine component is 1,9-nonanediamine, and the intrinsic viscosity [η] measured in concentrated sulfuric acid at 30 ° C. is 0.4 to 3.0dl / g der is, end
A base resin composition for electronic parts, which comprises polyamide in which 70% or more of the base is sealed . Wherein the electronic component based resin composition according to claim 1 consisting of 100 parts by weight 0.01 to 2 parts by weight nucleating agent polyamides.