JP3403470B2 - Phenolic resin composition for condenser sealing plate - Google Patents

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a phenol resin composition for a capacitor sealing plate. More specifically, the present invention relates to a phenol resin composition having good adhesion to a metal such as aluminum and having a low chloride ion content, which is suitable as a molding material for a capacitor sealing plate.

[0002]

2. Description of the Related Art Phenolic resin has electrical properties, mechanical properties,
Since the molded product has excellent heat resistance, flame resistance and chemical resistance, the molded product is used as a device or a part thereof in the fields of the electric and electronic industries. In the electric industry and other fields, it is used as a molding material for capacitor sealing plates. The capacitor sealing plate is manufactured by inserting an aluminum terminal into a mold and performing injection molding, transfer molding, compression molding or the like.

A conventional phenol resin molding material for a capacitor sealing plate is prepared by adding a reinforcing material to phenol resin and an organic filler such as pulp or wood powder as a filler.
The molding shrinkage ratio of the molded product is increased to improve the adhesion to the aluminum terminal. Further, there has been proposed a phenol resin composition used as a molding material for electronic parts such as coil bobbins whose chlorine ion concentration and ammonia concentration are limited to specific amounts or less. For example, Japanese Patent Publication 2-23576
In the publication, the chlorine ion concentration in the resin composition is 300 p.
Disclosed is an ammonia-free phenol resin composition for electrolytic corrosion resistance having a concentration of pm or less and an ammonia component concentration of 30 ppm or less. However, the phenol resin composition does not have sufficient adhesion to a metal such as aluminum,
Moreover, since the content of chlorine ions is not low enough, from the viewpoint of preventing contamination of the capacitor electrolyte,
It is not completely satisfactory as a molding material for a capacitor sealing plate.

From this background, the excellent characteristics of the phenolic resin are maintained, and when the molded product is used as a capacitor sealing plate, the adhesiveness to a metal such as aluminum is good and the electrolyte does not leak. A phenol resin composition that does not contaminate the capacitor electrolyte is desired.

[0005]

SUMMARY OF THE INVENTION The object of the present invention is to solve the above problems and to reduce the characteristics inherent to phenolic resins such as moldability, electrical characteristics, mechanical characteristics, heat resistance, flame resistance and chemical resistance. To provide a phenol resin composition for a capacitor sealing plate, which has good adhesion to a metal such as aluminum, prevents leakage of the capacitor electrolyte solution, and can prevent contamination of the capacitor electrolyte solution. is there.

[0006]

Means for Solving the Problems As a result of intensive studies to achieve the above-mentioned object, the present inventors have found that a composition obtained by adding a specific amount of resorcin and silicon oxide to a phenol resin has a chlorine ion content of Is a specific amount or less, the phenolic resin composition maintains the original properties of the phenolic resin, has excellent adhesion to metals such as aluminum, and found that it does not contaminate the capacitor electrolyte, Completed the invention.

That is, according to the present invention, 100 parts by weight of a phenol resin, 3 to 10 parts by weight of resorcin, and 50 to 15 of silicon oxide are used.
A phenol resin composition containing 0 part by weight and 100 to 200 parts by weight of glass fiber, wherein the chloride ion content of the resin composition is 50 ppm or less. is there.

The phenol resin composition for a capacitor sealing plate of the present invention is characterized by containing a specific amount of resorcin, silicon oxide and glass fiber, and having a chlorine ion content of 50 ppm.
In the following points, the capacitor using the capacitor sealing plate obtained from the phenol resin composition does not cause leakage of the electrolytic solution and does not contaminate the electrolytic solution of the capacitor.

The phenol resin composition for a capacitor sealing plate of the present invention will be described in detail below. The method for producing the phenolic resin composition for a capacitor sealing plate of the present invention is not particularly limited, and a commonly practiced method for producing a phenolic resin composition is applied. For example, a specific amount of resorcin, silicon oxide powder, and glass fiber is added to a phenol resin, and other additives such as a curing agent, a lubricant, and a coloring agent are added as necessary, so that the temperature at or near room temperature is increased. At temperature, after mixing using a mixer such as ribbon blender, Henschel mixer, kneader, mixing heat roll, kneading using a twin-screw extruder, etc., after further heat treatment if necessary, such as crusher, power mill A method of crushing using a crusher can be mentioned.

As the phenol resin used in the present invention, any of a resol type phenol resin, a novolac type phenol resin and an aralkyl phenol resin can be used. When the phenol resin contains a large amount of chlorine ions, the content of chlorine ions in the obtained phenol resin composition and the capacitor sealing plate is relatively increased, which causes contamination of the capacitor electrolyte. Considering this point, the amount of chlorine ions contained in the phenol resin composition of the present invention is 50.
It is important to be less than or equal to ppm. Preferably 30p
It is pm or less.

For example, when using a phenol resin obtained by using a catalyst containing chlorine ions such as hydrochloric acid and zinc chloride as a catalyst, the chlorine ion content is 30 pp.
Use a phenolic resin that is less than or equal to m. Therefore, when the phenolic resin used in the present invention is a novolac type phenolic resin or an aralkylphenolic resin, a phenolic resin polycondensed using oxalic acid or the like as a catalyst is preferable. After the polymerization reaction, washing with water or the like is preferably performed to reduce the content of chlorine ions and the like, and the content of chlorine ions is preferably 30 ppm or less.

The resorcin used in the present invention is used in an amount of 3 to 10 parts by weight based on 100 parts by weight of the phenol resin.
When the amount of resorcin added is small, the adhesion to a metal such as aluminum is not sufficient, which causes leakage of the capacitor electrolyte when used as a capacitor sealing plate. Also,
If the amount is too large, the curing rate of the phenol resin is significantly accelerated, resulting in deterioration of moldability. Considering this point, the addition amount is selected from the above range.

The silicon oxide used in the present invention may be crystalline or amorphous. When the amount of silicon oxide added is small, the surface smoothness of the obtained capacitor sealing plate is poor, and when it is large, the mechanical strength of the capacitor sealing plate is reduced. In consideration of this point, the amount of silicon oxide added is 50 to 150 with respect to 100 parts by weight of the phenol resin.
It is selected from the range of parts by weight. A high chlorine ion content in silicon oxide is not preferable because it causes contamination of the capacitor electrolyte. From this point of view, the chloride ion content of silicon oxide is preferably 30 ppm or less. Further, if the particle size of silicon oxide is large, the surface of the obtained sealing plate becomes rough and the surface condition deteriorates. From the point of view, the particle size of silicon oxide is preferably 50 μm or less. More preferably 2-10
It is in the range of μm.

The glass fiber used in the present invention has a fiber diameter of 3 to.
Chopped strands having a thickness of 13 μm and a fiber length of 0.2 to 6 mm are preferably used. Further, glass fibers surface-treated with an aminosilane coupling agent or the like are preferable because the adhesion with the phenol resin is improved. If the amount of glass fiber added is small, the strength of the resulting capacitor sealing plate will be low, and if it is large, the kneading properties will be poor during the production of the phenol resin composition, and the heat in the cylinder when injection molding, for example, will be performed. Stability decreases. Considering this point,
The amount of glass fiber added is selected from the range of 100 to 200 parts by weight with respect to 100 parts by weight of the phenol resin.

The phenol resin composition for a capacitor sealing plate of the present invention comprises the phenol resin, to which a specific amount of resorcin, silicon oxide and glass fiber are added as described above.
It is obtained by mixing and kneading. However, when the phenol resin composition for a capacitor sealing plate of the present invention is produced using the same equipment and device after producing the phenol resin composition used for other purposes, a mixer, a kneader, etc. May be contaminated with chlorine ions, so it is preferable to prevent the contamination of chlorine ions by washing the entire process.

If desired, the phenol resin composition for a capacitor sealing plate of the present invention may further contain other additives such as a curing agent, a lubricant and a coloring agent. Hexamethylenetetramine (hereinafter abbreviated as hexamine) is usually used as the curing agent. The amount of hexamine used is 8 to 18 parts by weight based on 100 parts by weight of the novolac type phenol resin. If it is less than 8 parts by weight, the cross-linking density of the phenol resin is low and the mechanical strength is lowered, and if it exceeds 18 parts by weight, bubbles may be contained in the obtained capacitor sealing plate and the surface condition is deteriorated. It is not necessary to add the curing agent when the resol-type phenol resin is used alone or when the novolac-type phenol resin and the resol-type phenol resin are used in combination.

The lubricant is not particularly limited, but higher fatty acids such as stearic acid and palmitic acid, alkaline earth metals (calcium salts, magnesium salts, etc.) of the higher fatty acids.
Alternatively, montanic acid wax and higher fatty acid amides can be used. The amount of lubricant used is phenol resin 100
It is 0.5 to 5 parts by weight, preferably 2 to 3 parts by weight with respect to parts by weight. If it is less than 0.5 part by weight, the effect as a lubricant is small, and if it exceeds 5 parts by weight, the adhesion between the phenol resin composition and a metal such as aluminum is deteriorated, which is not preferable.

As the colorant, carbon black, molybdenum red, phthalocyanine blue or the like is appropriately selected and used.

The curing agent, lubricant and colorant may be added at the same time when resorcin, silicon oxide and glass fiber are added to the phenol resin, or they may be added later to the resin composition to which they are added. You may. The thus obtained phenol resin composition for a capacitor sealing plate of the present invention can be applied to any molding method such as compression molding, injection molding and transferer molding.

[0020]

EXAMPLES The present invention will be described in more detail below with reference to examples. Example 1 <Preparation of resin composition> Novolak type phenol resin polycondensed using oxalic acid as a catalyst (Mitsui Toatsu Chemicals, Inc.)
Made, product name: # 500HX, chlorine ion content: 7pp
m) 100 parts by weight, resorcin (Mitsui Petrochemical Co., Ltd.)
5 parts by weight, hexamine (manufactured by Mitsui Toatsu Chemicals, Inc., trade name: S-4) 15 parts by weight, silicon oxide powder (manufactured by Tsuchiya Kaolin Industry Co., Ltd., trade name: Crystallite A-1, chlorine) Ion content: 10 ppm) 50 parts by weight, glass fiber (Nippon Electric Glass Co., Ltd., trade name: ECS-03B-1)
54 HP, surface treated product with aminosilane coupling agent, fiber length: 1 to 6 mm, fiber diameter: 6 to 13 μm, chloride ion content: 6 ppm) 150 parts by weight, calcium stearate 2.5 parts by weight, carbon black (Showa Carbonate ( Ltd., trade name: Showbra T-0) 2 parts by weight were mixed for 10 minutes at room temperature using a ribbon blender. The obtained mixture is a front roll 95 ℃, a rear roll 50 ℃
Roll kneading was carried out for about 3 minutes using the mixing roll No. 1.
The obtained kneaded product was pulverized with a power mill (manufactured by Dalton Co., Ltd.) to obtain a phenol resin composition. Table 1 shows the types of the phenolic resin and the additives and their respective mixing ratios (parts by weight).

<Molding of Capacitor Sealing Plate> Using an injection molding machine (manufactured by Toshiba Machine Co., Ltd., model: IR-45P),
Cylinder temperature 1st zone 95 ° C, 2nd zone 60 ° C,
Mold temperature 180 ℃, injection pressure 1000-1500 kg /
cm ² and a screw rotation speed of 50 rpm,
A capacitor sealing plate having an aluminum terminal inserted was molded.

<Evaluation of Characteristics of Resin Composition> Test pieces for various characteristics evaluation were prepared from the obtained phenol resin composition by the following methods, and various mechanical characteristics and thermal characteristics were evaluated by the following methods using the test pieces. did. The obtained results are shown in [Table 2].

(1) Method for preparing test piece By injection molding under the same conditions as the molding of the above-mentioned capacitor sealing plate, according to the method specified in JIS-K6911, the obtained phenol resin composition was used for bending test. A test piece, a mold shrinkage test piece, and a flame retardancy test piece are prepared. For the test piece for linear expansion coefficient, the test piece for bending test described above is cut to form a test piece having a length of 3 mm, a width of 3 mm, and a thickness of 3 mm.

[0024] (2) line for measuring the above methods specimen obtained bending test for measuring test piece created by the expansion coefficient, thermal analyzer (Rigaku Corporation, Ltd., type: TG-8110) using a nitrogen atmosphere The measurement is performed at a heating rate of 5 ° C./min.

(3) Method for measuring bending strength, molding shrinkage and flame retardancy: Measured according to the method specified in JIS-K6911.

[0026]

( 4 ) Method for measuring total chlorine ions in the composition: 3 to 5 mg of a sample is burned in an oxygen frass, the generated gas is absorbed in an aqueous sodium hydroxide solution, and the resulting absorbing solution is subjected to an ion chromatography method ( Made by DIONEX, type: A
G-4A) to analyze and quantify total chlorine ions.
(Ppm)

( 5 ) Method for measuring adhesion between phenol resin composition and aluminum terminal The capacitor sealing plate obtained above is attached to a capacitor container and the internal pressure is increased to 0.3 kg / cm ² . The capacitor is immersed in water, and the presence or absence of air bubbles is visually observed from the aluminum terminal portion, and the one in which air bubbles are observed is regarded as defective. 100 pieces are tested and shown by the defect occurrence rate.

Examples 2 to 4, Comparative Examples 1 to 5 In Example 2, a resol type phenol resin (manufactured by Gunei Chemical Co., Ltd., trade name: N-411) was used, and Examples 3 to 3 were used.
In No. 4 and Comparative Examples 1 to 5, the same novolac type phenolic resin as in Example 1 was used. A phenol resin composition was obtained in the same manner as in Example 1 except that the additives were added in the mixing ratios (parts by weight) shown in [Table 1] to 100 parts by weight of each phenol resin. Each characteristic of the obtained resin composition was evaluated in the same manner as in Example 1. The compounding ratio of the phenol resin composition is shown in [Table 1] and the characteristic evaluation result is shown in [Table 2].
Or shown in [Table 3].

[0030]

[Table 1]

[0031]

[Table 2]

[0032]

[Table 3]

[0033]

EFFECT OF THE INVENTION The phenol resin composition for a capacitor sealing plate of the present invention provides a capacitor sealing plate having good adhesion to metal terminals such as aluminum. Therefore, the capacitor sealed with the sealing plate does not leak the electrolytic solution.
Further, since the chloride ion content in the composition is low, the capacitor electrolyte is not contaminated. Therefore, by using the sealing plate obtained by molding the phenol resin composition for a capacitor sealing plate of the present invention, the performance of the capacitor is not deteriorated.

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A 61-187218 (JP, A) JP-A 3-190954 (JP, A) JP-A 4-46947 (JP, A) JP-A 61- 296051 (JP, A) JP 60-127347 (JP, A) JP 61-113641 (JP, A) JP 63-238150 (JP, A) JP 7-113035 (JP, A) International Publication 93/14511 (WO, A1) (58) Fields investigated (Int.Cl. ⁷ , DB name) C08L 61/04-61/16 H01G 4/224 WPI / L (QUESTEL) CA (STN) REGISTRY ( STN)

Claims (3)

(57) [Claims] 1. A phenol resin composition containing 100 parts by weight of a phenol resin, 3 to 10 parts by weight of resorcin, 50 to 150 parts by weight of silicon oxide, and 100 to 200 parts by weight of glass fiber, wherein chlorine ion of the resin composition. Content is 50p
A phenol resin composition for a capacitor sealing plate, which has a pm or less. 2. A phenol resin having a chloride ion content of 3
It is 0 ppm or less, The phenol resin composition for capacitor sealing plates of Claim 1 characterized by the above-mentioned. 3. The chlorine ion content of silicon oxide is 30 pp.
The phenol resin composition for a capacitor sealing plate according to claim 1, wherein the phenol resin composition is less than or equal to m.