JPH01161819A - Separator for electrolytic capacitor - Google Patents

Abstract

PURPOSE:To make it possible to manufacture an electrolytic capacitor characterized by a low equivalent series resistance value and excellent sound quality, by including floss silk in at least a part. CONSTITUTION:The raw material of floss silk is cocoons. The thickness of the fiber is as thin as 1/5-1/100 that of Manila hemp. The bends of the fiber is complex. The thickness are not uniform. Only the floss silk can hold sufficient amount of electrolyte by cutting, beating, paper manufacturing and so forth. Since the quality is close, an electric resistance can be made small when the electrolyte is impregnated. When the floss silk is mixed with vegetable fiber such as Manila hemp and craft in order to increase mechanical strength and to make mixed paper, the floss silk fiber is finely entangled in the gaps between the thick fibers of the Manila hemp and the craft. Thus the very thin gaps are formed. The withstand voltage of a separator, which is electrolytic paper, is improved. When the separator including the floss silk fiber is used, repelling force is less since the separator is soft against minute bending force caused by vibration. Therefore, deterioration in audio signals and distortion in sound quality can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a separator in an electrolytic capacitor in which an anode foil and a cathode foil made of aluminum foil or the like are laminated or wound with a separator in between.

[Prior Art] Generally, an aluminum electrolytic capacitor is manufactured by laminating an anode foil and a cathode foil made of aluminum foil with a separator in between, or by impregnating a wound capacitor element with an electrolytic solution and assembling it together with a sealing body in an exterior case. It has an intricate structure.

In such a laminated type or wound type electrolytic capacitor, a separator is used to retain a sufficient amount of electrolyte and to prevent a short circuit between the two electrodes. The material for manufacturing the separator is vegetable fiber or synthetic resin fiber.

Most separators made of vegetable fibers are kraft paper or Manila hemp paper. In addition, items made from the Indian solar layer and items made from cotton are also used. Although kraft paper is inexpensive and strong, it has the disadvantage that since ja#i is flat, the current path after being impregnated with an electrolyte becomes long and the electrical resistance value increases. Manila hemp paper has the advantage of reducing resistance because the shape of the 1a fibers is a little closer to a circle than kraft paper, making the current path shorter, but it is expensive. Papers made from a mixture of kraft and manila hemp are also used.

Materials for the separator made of fiber include polypropylene, vinylon, rayon, polyethylene,
Polyester, etc. Such synthetic fibers can be obtained with a fiber shape that is close to a perfect circle, so they can have a low resistance value after being impregnated with an electrolyte, but it is said that a material with good paper properties is advantageous. Due to its drawbacks, it is often used as a mixed paper with kraft or manila hemp.

[Problems to be solved by the invention] Electrolytic capacitors using separators as described above still have a high resistance value and a small amount of electrolyte retention, and when viewed as electrolytic capacitors, electrical performance at room temperature and low temperature is low. Due to its high resistance value, it has caused problems when used in switching power supplies. In addition, when electrolytic capacitors are used as power supply smoothing capacitors or coupling capacitors for audio equipment, they have a high resistance value with respect to frequency, and are difficult to absorb internal and external vibrations.
It has become difficult to prevent audio signal deterioration and sound quality distortion.

[Means for Solving the Problems] However, in order to solve the above-mentioned problems, the present invention provides a separator containing cotton cotton.

The raw material for cotton cotton is cocoon, and since the wood fibers are as thin as Manila hemp I75 to 17100, and the fibers have complicated bends and are uneven in thickness, cotton is made from cocoon through cutting, beating, paper-making, etc. Even when used alone, the amount of electrolyte retained is improved, and since it is dense, the electrical resistance value when soaked with electrolyte can be reduced. In addition, when making mixed paper by incorporating vegetable fibers such as manila hemp and kraft in order to strengthen the mechanical strength, the cotton fibers are tightly entangled in the gaps between the thick fibers of manila hemp and kraft, and the very thin gaps are , the withstand voltage of the separator, which is electrolytic paper, is improved. It was also found that the electrical resistance value when impregnated with electrolyte was significantly smaller than that of Manila hemp or kraft alone. Also,
According to a separator containing cotton fibers, the separator is soft and has little repulsive force against minute bending forces caused by vibrations, and therefore can prevent deterioration of audio signals and distortion of sound quality.

The separator according to the present invention is made of cotton fiber Totai,
It is made of a mixture of other vegetable fibers, synthetic resin fibers, glass fibers, or mixed fibers thereof.

[Examples] Example 1 A single fiber separator made of cotton cotton with an average fiber diameter of 1 μm was prepared with a thickness of 60 μm and a density of 0.6 g/cm'. The tensile strength is 2.1 kg and the width is 715 mm.
When this separator is impregnated with a γ-butyrolactone electrolyte, the equal series resistance (ESR) is 0. It was lOΩ. In addition, this equal series resistance value is 20℃, 120Hz
This is from the time of.

Example 2 70% cotton fiber with an average fiber diameter of 1 μm and an average fiber diameter of 10 μm
A separator made of 30% manila hemp with a thickness of 60 μm and a density of 0.6 g/cm' was prepared. The tensile strength is 2.7 kg and 715 mm width, and when impregnated with γ-butyrolactone electrolyte at 20°C and 120 Hz.
The ESR at this time was 1.20Ω.

Reference Example A separator made of manila hemp with an average fiber diameter of 10 μm and a thickness of 60 μm and an I1 degree of 0.6 g/cm was prepared. ESR was 1.80Ω.

Next, an aluminum capacitor with a rating of 50V and a capacity of 100gF was created using the separator described above, and the equivalent series resistance (4 (ESR) at 20°C
) was measured.

The results are shown in Table 1.

Table 1 Frequency characteristics When a vibration of 1kllz is applied to these electrolytic capacitors, the 3rd harmonic distortion rate when a signal of 1kllz is input was investigated, and it was found that the 3rd harmonic distortion rate of Example 2 was higher than that of the reference example. , was found to decrease by 4 to 5 dB.

In addition, when these electrolytic capacitors were used in the coupling circuit of a CD player and listened to with different attachments, it was found that the distortion in the high-frequency sound quality of the example 2 was significantly reduced compared to the reference example. The amount of information in the sound has increased significantly, resulting in a well-balanced, high-quality sound.

[Effects] As described above, according to the separator of the present invention containing cotton in at least a portion, it is possible to provide an electrolytic capacitor with a low equal series resistance value and an electrolytic capacitor with good sound quality.

In addition to aluminum electrolytic capacitors, the separator according to the present invention can also be used for energy storage devices such as electric double layer capacitors, solid electrolytic capacitors, other special capacitors, secondary batteries, secondary batteries, and other special batteries. It can be used as a separator.

Claims (1)

[Claims] (1) A separator for electrolytic capacitors containing at least a portion of cotton.