JPS6121153A - Phenolic resin composition - Google Patents

Abstract

PURPOSE:A composition, consisting of a resol resin, soft ferrite, and glass fibers, and having improved heat and metal corrosion resistance, amplification of magnetic flux, shielding property and moldability. CONSTITUTION:A phenolic resin composition obtained by incorporating 5- 15pts.wt. resol resin with 75-90pts.wt. soft ferrite and 5-10pts.wt. glass fibers. A solid resol having 400-800 number-average molecular weight is preferred for the resol resin. Soft ferrite having <=20mum particle diameter and nickel based (<=1MHz electromagnetic waves) or manganese based (20kHz-1MHz electromagnetic waves) is preferred for the soft ferrite. Glass fibers primarily treated with a silane coupling agent are preferred for the glass fibers.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a phenolic resin composition that has excellent heat resistance, metal corrosion resistance, increased magnetic flux, shielding properties, and moldability.

[Prior art]

Recently, there has been an active movement toward higher functionality and higher performance of resins, regardless of whether they are thermoplastic resins or thermosetting resins.

There are two ways to impart functionality: modifying the resin itself and combining it with functional fillers; however, in the case of thermosetting resins, the latter method is often used, taking advantage of the resin's own characteristics. It is taken.

Normally, to obtain a ferrite molded product, a mixture of ferrite powder and a binder such as a resin is shaped in advance using a press or the like, and then fired and sintered in an electric furnace. There are problems with cracking and chipping during firing, long firing times, and dimensional accuracy of the product, and it is difficult to manufacture products with complex shapes.

In addition, when the content of filler is high, there is a method of using a low viscosity liquid resin as a binder, casting it in a mold and curing it to obtain a molded product, but when using a material with a high specific gravity such as ferrite, the resin and ferrite may be mixed. There was a drawback that it was difficult to separate and obtain a uniform molded product.

[Purpose of the invention]

In view of the above circumstances, the present invention has been developed as a result of intensive research to develop a material that solves the above problems and imparts the above characteristics.

The object of the present invention is to provide a material with excellent heat resistance, metal corrosion resistance, magnetic flux amplification and shielding properties, and moldability.

[Structure of the invention]

The present invention is made by manufacturing a mixture consisting of 5 to 15 parts by weight of resol resin, 75 to 90 parts by weight of soft ferrite, and 5 to 10 parts by weight of glass fiber using a mixer such as a hot roll, a co-kneader, or a twin-screw extruder. This invention relates to phenolic resin molding materials.

Any resin can be used as long as it is a resol type phenolic resin, but it is especially suitable for molecular weight (Kl
A solid resol having an n-number average molecular weight of 400 to 800 is preferred because of its excellent moldability, dimensional accuracy, and material storage stability.

Although it is possible to use Novo 2 Tsuku type phenolic resin as a material, it is not preferred because it has the problem of corroding metals due to ammonia gas remaining inside the molded product and unreacted hardening agent, and has the disadvantage of poor heat resistance. In addition, epoxy resin, polyester resin, etc. do not have the problem of metal corrosion, but they have heat resistance and
There are problems with moldability, cost, etc., and it is not practical.

The blending amount of the resol resin is preferably 5 to 15 parts by weight. If it is less than 5 parts by weight, it is impossible to make it into a material, and if it is more than 15 parts by weight, there are problems such as adhesion of the material to equipment and difficulty in controlling the fluidity of the material. This is because there is.

Glass fiber is indispensable because it is useful for improving heat resistance and improving workability when making materials using rolls, co-kneaders, extruders, etc. Moreover, any commercially available chopped stride glass fiber having a fiber length of 1 to 5 mm and a fiber diameter of 8 to 15 mm can be used. Generally, commercially available chopped strands are primarily treated with a silane coupling agent, but heat resistance can be further improved by using the glass fibers after a second treatment with a silane coupling agent. If the amount added is less than 5 parts by weight, there is no effect, and if the amount added is more than 10 parts by weight, the problem arises that the dispersibility in the material becomes poor. Therefore, the amount of glass fiber blended is preferably 5 to 10 parts by weight.

Soft ferrite is composed of components such as iron oxide, zinc oxide, manganese oxide, etc., or iron oxide, zinc oxide, nickel oxide, etc., and there are grades of various compositions depending on the purpose, but the particle size is 20 μm. Any of the following can be used. Thicknesses of 20 μm or more are not preferable because they cause problems in appearance, moldability, etc. of molded products.

Regarding electromagnetic properties such as magnetic flux amplification and shielding effect of the molded product, factors determined by the type of soft ferrite and the lid contained are preferably <75 to 90 parts by weight. Moreover, the types are used depending on the frequency band of the electromagnetic waves.

That is, nickel-based soft ferrite is effective at IMHz or higher, and manganese-based soft ferrite is effective at 20 KHz to 1 MHz.

〔Effect of the invention〕

The phenolic resin molding material obtained as described above is molded by heating and pressurizing it by a commonly used molding method such as compression molding or transfer molding.

This phenolic resin molding material has good moldability because the types and amounts of ferrite and glass fibers contained in it are regulated, and it has excellent heat resistance, metal corrosion resistance, magnetic flux amplification, and shielding properties. It is possible to obtain a molded product.

〔Example〕

Parts by weight are hereinafter abbreviated as parts.

(Example 1) 113 parts of Resol PR-5114 manufactured by Sumitomo Delez ■, 79.5 parts of manganese soft ferrite manufactured by Toda Kogyo ■, 7 parts of Asahi Fiberglass ■ 3M long glass fiber, and 0.5 part of stearic acid were blended, A molding material was made by dry roll kneading.

(Example 2) Phenol and paraform were blended so that the molar ratio F/P (F: formaldehyde, P: number of moles of phenol) was 1.30, and an addition condensation reaction was performed using manganese acetate as a catalyst. , 10 parts of dimethylene ether type resol obtained by dehydration under reduced pressure, 5 parts of Nippon Glass Fiber ■ 6 m long glass fiber, 84.5 parts of nickel-based soft ferrite manufactured by Tohoku Metal Industry ■, 0.5 part of stearic acid. The mixture was blended and melted and kneaded using an Ikegai Iron Works extruder to produce a molding material.

(Example 3) 15 parts of Resol PR-51549 manufactured by Sumitomo Delez ■, 9 parts of 1.5-length glass fiber manufactured by Nippon Electric Glass ■, TDK ■
A molding material was prepared by blending 75.5 parts of manganese-based soft ferrite and 0.5 part of stearic acid by dry roll mixing.

(Comparative Example 1) 7 enols were added so that the molar ratio F/P was 0.80,
12 parts of novolak resin, 2 parts of hexamethylenetetracarbon, and 3 m long glass from Nippon Glass Fiber, which were obtained by blending formalin and carrying out an addition condensation reaction using citric acid as a catalyst, followed by dehydration under reduced pressure. 7 parts of fiber, 77.5 parts of Toda Kogyo's manganese soft ferrite, and 5 parts of stearin #IO were mixed and melted and kneaded using an Ikegai Iron Works extruder to produce a molding material.

(Comparative Example 2) Dainippon Ink & Chemicals Polyester Resin PB-9
6010 parts, curing agent Dikier ruber oxide 0.5
Contains 8 parts of Nippon Glass Fiber, 6 m @ long glass fiber, 81 parts of manganese-based soft phe2ite, and 0.5 parts of zinc stearate. AST8[)648 0.5 f copper wire
It was wrapped around a heat deformation test piece of 40℃ and 90℃.
% corrosion after being placed in a constant temperature and humidity chamber for 30 days.

Note 2) Regarding electromagnetic characteristics, a high-frequency current in the range of 20 KHz to 20 MHz is passed through the copper wire, and a 100 f x 3 m test piece is placed at a distance of 21+@ to measure the generated magnetic flux. Evaluated by machine.

Note 3) The moldability was tested using Lancefer and Combrege carbon evaluation molds (created by Sumitomo Bakelite ■).

Note 4) The heat distortion temperature is based on ASTM D648, and the bending strength and Charpy impact strength are based on JISK6911.

According to the results in the table above, Examples 1.2.3 have strength,
It is confirmed that heat resistance, metal corrosion resistance, electromagnetic properties, and formability are well balanced.

Claims (1)

[Claims] 5-15 parts by weight of resol resin, 75-15 parts by weight of soft ferrite
A phenol resin composition comprising 90 parts by weight and 5 to 10 parts by weight of glass fiber.