Nomura Micro Science Co., Ltd.

Asahi Kasei Chemicals Corporation

Mutsuko Endou

Takashi Ito

Takazou Hirose

Kazunari Akahira

Yasuo Kousaka

Tooru Kusano

Seiichi Inagaki

Motonori Yanagi

A method for measuring the number of fine particles in ultrapure water includes subjecting the ultrapure water to internal pressure filtration through a hollow fiber membrane having a skin layer capable of trapping the fine particles in the ultrapure water at least on an inner surface thereof, exposing the inner surface of the hollow fiber membrane, and measuring the number of fine particles on the exposed inner surface.

Method for measuring the number of fine particles in ultrapure water and method for manufacturing a filtration device for measuring the number of fine particles in ultrapure water

A novel measuring method which allows measurement of fine particles which are extremely fine and contained in a very small amount in ultrapure water is provided. The number frequency with respect to the fine particles having a particle diameter of 0.1 &#x3bc;m or more is measured based on the finding that the fine particles contained in the ultrapure water at the use point of an ultrapure water production system exhibits a logarithmic normal distribution to determine the logarithmic normal distribution of the fine particles contained in the ultrapure water, and the number of the fine particles having a particle diameter of less than those of the measured particles contained in the ultrapure water is obtained from the distribution.

Method and device for measuring fine particles in ultrapure water

Growing community of inventors

Atsugi, Japan

Mutsuko Endou