JPS5827499A - Diaphragm for speaker - Google Patents

Abstract

PURPOSE:To eliminate deterioration for the use at a long period, by improving the corrosion-proof and solvent-proof performance of a diaphragm plate through a surface layer, which is formed with a colloidal silicon oxide and a silicon resin including much silicon composition heated and cured on the surface of a metallic foil diaphragm. CONSTITUTION:On the surface of a metallic foil diaphragm 3 which is light and excellent in the specific elasticity but lacks in the corrosion-proof, a colloidal silicon oxide and a silicon resin including much silicon composition are heated and cured to form a surface layer 4. The reaction between the silicon resin and the colloidal silicon oxide is progressed with this curing to strengthen the bonding beween the metallic foil and the diaphragm. The corrosion proof of the diaphragm is improved and crack and exfoliation of the surface layer 4 due to thermal shock can be avoided and the deterioration of quality for a long time use can be avoided, allowing to keep stable quality and to improve the reliability.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a speaker diaphragm constructed using metal foil.

It was common.

However, this speaker diaphragm made of natural pulp fibers was unsatisfactory in terms of physical properties, such as high rigidity and high specific elastic modulus, which are necessary for speaker characteristics. In addition, it has poor moisture resistance and has many problems such as deterioration of sound quality in a humid atmosphere.

For this reason, speaker diaphragms made of light metal tracks such as aluminum foil have been developed.

However, metal foil diaphragms have problems such as poor appearance and changes in sound quality due to deterioration of the material due to corrosion. Corrosion caused by salt, etc. was particularly severe, and if you touched the speaker diaphragm directly with your hand, it would leave fingerprints, which would corrode the area and give it a poor appearance. Moreover, over many years, changes in the material of the metal foil may cause changes in sound quality.

In recent years, as shown in Fig. 1, aluminum foil diaphragm 1 has been used.
A type in which a thin resin layer 2 is provided on the surface of the aluminum foil has also been developed, but the adhesion between the aluminum foil and the resin layer 2 is poor, it lacks heat resistance, and it cannot be said to be fully satisfactory in terms of corrosion resistance. Met.

The present invention aims to eliminate the above-mentioned conventional drawbacks and relates to a speaker diaphragm that has been subjected to a surface treatment that has excellent corrosion resistance and excellent adhesion to metal foil.

That is, the speaker diaphragm of the present invention has a structure in which a surface layer formed by heating and curing colloidal silicon oxide and silicone resin with a high silicon content is provided on the surface of a metal foil diaphragm. be.

Hereinafter, an embodiment of the speaker diaphragm of the present invention will be described with reference to FIG. 2.

In Fig. 2, numeral 3 denotes a metal foil diaphragm formed into a cone shape using a metal foil such as aluminum, aluminum alloy, beryllium, or beryllium alloy, which is lightweight, has poor corrosion resistance, and has an excellent specific elastic modulus. A surface layer 4 is formed on the surface of the plate 30. This surface layer 4 is made by dispersing silicon resin with a high silicon content and colloidal silicon oxide in methyl cellosolve and methyl cellosolve, and the silicon resin has a silicon content of approximately 1Q to 13
wt%, and after applying the treatment agent to metal foil such as aluminum, the solvent content is volatilized and the temperature is 130"C to 180".
10 to 40 minutes at a temperature of 150°C, preferably 150°C.
By heating and curing for 0 minutes, the resin reacts with colloidal silicon oxide, and strong adhesion is obtained by bonding with metal foil such as aluminum.

When aluminum foil is immersed in an undiluted solution with a solid content of approximately 30 wt% (silicon oxide and silicone resin) and heated and cured, the thickness of the surface layer 4 becomes 4 to 6 μm, and this surface layer 4 is extremely strong and corrosion resistant. , it has excellent heat resistance.

The surface treatment agent mentioned above is VES TAR treatment agent (
A comparison of various characteristics with a commercially available diaphragm (manufactured by Dow Corning, USA) and a commercially available diaphragm is shown below.

[Corrosion resistance]

A 5% solution of sodium chloride was prepared and tested for corrosion resistance by salt spray test.

0 Aluminum base Fully corroded after 12 hours Exposed diaphragm/acrylic resin coating Corrosion occurred after 24 hours (10
[Heat resistance] 1 OO'C, 1 CSO'C, 200'C ( 7) The state of the film was observed under each temperature condition.

100°C 150'C 200°C O 3 μm Aluminum 10 μm Acrylic ζ Niwam Vibration Note that no abnormality was observed in the speaker diaphragm of the present invention even at 260'C.

[Thermal shock resistance]

After being left in an atmosphere of 100"C, 150°C, 200"G, and 250'C for 1 hour, it was immediately put into water at 20-25°C and the state of the film was observed.

100'C150'C200'C260°CO Aluminum with 3μm alumite layer Good Cracks Cracks Cracks Miniram diaphragm 010μm acrylic of the present invention with 6μm surface layer formed Good Good Good Good Atsubenium diaphragm [Solvent resistance] Book The speaker diaphragm having the surface layer of the invention showed no change at all when exposed to alcohol-based and organic solvents.

Since the speaker diaphragm of the present invention is constructed as described above, the corrosion resistance of the surface layer is improved even when the metal foil is used as the base, and the surface layer does not crack or peel due to thermal shock. It also has excellent solvent resistance and can maintain extremely stable quality without deterioration even after long-term use, making it highly reliable and of great industrial value.

[Brief explanation of drawings]

Figure 1 is a half-sectional front view of a conventional speaker diaphragm;
The figure is a half-sectional front view of the speaker diaphragm of the present invention. 3...Metal foil diaphragm, 4...Surface layer 0
Name of agent: Patent attorney Toshio Nakao and one other person
l diagram

Claims (1)

[Claims] A speaker vibration device that is made by providing a surface layer formed by heating and curing colloidal silicon oxide and silicone resin with a high silicon content on the surface of a lightweight metal foil diaphragm that has excellent specific elastic modulus and poor corrosion resistance. Board.