[Realization of a request] Improvement in quality

  • Design development based on basic research

  • Tenacious researchers

  • Innovation of pulverizing technique

  • Establishment of the evaluation system and introduction of equipment that were not used conventionally

Results from long-term basic research has led to an improvement in quality


A customer consulted us regarding whether we could improve the electric insulation performance of mica tape by 20% or more than the existing performance to increase the output of their product.

The mica tape that makes up the electrical insulation layer is made from mica foil, glass cloth and adhesive. To meet our customer’s request, we attempted an approach focused on the optimization of mica paper.

To meet the customer’s request, glass cloths or adhesives may easily be adjusted as a minor change.
Improvements made in the characteristics of mica paper is close to a full-model change. Furthermore, we, even as a mica manufacturer, could not fully understand how we could alter the design to meet their request in this case. We considered this a shameful thing, and decided to set the basic policy of development as "restarting as a mica manufacturer and re-starting from the basics" and began development. Thorough basic research was carried out, starting with the analysis of the shape of each mica particle on the order of microns and then analyzing the laminated structure of mica paper. In addition, we actively introduced new evaluation methods and systems similar to our customers so that we could correlate them with our customer’s evaluation results.
Eventually, we found that conventional mica paper had weaknesses that had a negative effect on insulation performance, and by eliminating these weaknesses we were able to solve the problem.
However, in order to eliminate these weaknesses, the cost of mica paper had to be significantly increased.
Therefore, it was necessary to find a pulverization method that would not cause this weakness, so we made a major design change from the conventional mica raw ore pulverizer.
From the theme of material design and development to the theme of production technology development of a pulverizer, we were able to finally finish a mica tape that satisfies QCD.


At first, we began development aimed at improving the design method. However, it was found that the conventional mica paper itself needed to be improved, and finally, a new pulverizer was used to realize the pulverization method identified through our research. We really felt that a number of accumulated patient studies through the development project led to innovation.

We succeeded at eliminating the "weak point" that adversely affected the insulation performance with the originally developed pulverizer.