JPH0151289B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for cutting a multilayer capacitor. Many types of cutting methods for multilayer capacitors have been considered; for example, Japanese Patent Application Laid-Open No. 51-150664
The publication can be said to be a relatively new cutting method. This publication is characterized by the use of a polyolefin resin film as a lubricant, but if the sawed area of the multilayer capacitor is larger than 4 ^cm2 , even if the thickness of the polyolefin resin film is extremely thick, the cut surface It is difficult to stop the burn-in. Furthermore, feeding the polyolefin resin film during cutting has the disadvantage of complicating the structure of the cutting machine. The present invention does not cause seizing of the cut surface even when the sawing area is large, and the electrical insulation withstand voltage of the cut surface is superior to that of conventional cutting methods using wax or cutting oil, and the insulation resistance value is high. This invention provides a method for cutting a multilayer capacitor. The details of the present invention will be described below. The method for cutting a multilayer capacitor according to the present invention is to use polybutene as a lubricant in the cut portion when cutting with a saw blade. Thereby, it is possible to obtain a multilayer capacitor with excellent electrical insulation breakdown voltage at the cut surface even when immersed in cutting. This method is particularly advantageous in the case of capacitors in which the dielectric is a Lacquer film. This is because in the case of a Lacquer thin film, the dielectric melts at a lower temperature than in a normal stretched film, which tends to cause a decrease in insulation resistance, but polybutene penetrates between the layers of the Lacquer thin film, causing a decrease in insulation resistance. prevent. Also wax,
It has superior cooling performance compared to polyolefin resin, and is less likely to corrode the Lutzker thin film than normal cutting oil. Specific examples will be described below. Example A base capacitor is made by winding a 4 μm thick double-sided metallized polyester film coated with a 0.8 μm thick polycarbonate lacquer thin film on each surface, and then this base capacitor is assembled into units using various lubricants. Cut into a capacitor. The sawed area was 2 cm ² , and insulation evaluation was performed based on the rate of decrease in capacitance of the capacitor before and after applying a DC voltage of 200 V. The results are shown in the table below.

【table】

[Table] As is clear from the above table, liquid lubricants are superior to solid lubricants. However, the Lutzker thin film was attacked by mineral oil, and the insulation resistance value decreased. As clarified above, the method for cutting a multilayer capacitor according to the present invention has the effect of improving the electrical insulation breakdown voltage of the cut surface and not reducing the insulation resistance.

Claims (1)

[Claims] 1. A method for cutting a multilayer capacitor, which comprises using polybutene as a lubricant when cutting a multilayer capacitor in which a base capacitor made of a metallized film is cut with a saw to obtain unit capacitors.