Riso Kagaku Corporation

Dainippon Ink and Chemicals, Incorporated

Nec Personal Computers, Ltd.

Toshiaki Kano

Hiroshi Matsuda

Mitsuo Kase

Ichiro Muramatsu

Takahiro Funayama

A keyboard device has a base sheet, a membrane sheet disposed on the upper surface of the base sheet, a cover sheet disposed on the upper surface of the membrane sheet and supporting the membrane sheet between the cover sheet and the base sheet in a state of being movable in the in-plane direction, connection members connecting the base sheet and the cover sheet, a plurality of key tops vertically movably supported by a guide mechanism provided on the upper surface side of the cover sheet and bringing a movable contact and a fixed contact which are contacts of the membrane sheet into contact with each other or separating the contacts from each other by being depressed, and a frame member partitioning the key tops adjacent to each other by being depressed and having a lower surface to which the upper surface of the cover sheet is bonded and fixed.

Keyboard device and electronic apparatus

A finely particulate polymer for use in a stencil ink is disclosed which is uniformly dispersible into a binder polymer having a solubility parameter of 11.0 or lower and has an average particle diameter of from 0.1 to 10 .mu.m and a maximum particle diameter of 50 .mu.m or smaller. The finely particulate polymer is highly advantageous in that stencil inks having an appropriate viscosity can be easily obtained with the particulate polymer using the same formulation even when the inks contain different colorants, and that with the particulate polymer, a colorant which has been unusable due to its adverse influence on the storage stability of stencil inks can be used to produce a stencil ink having excellent storage stability by encapsulating the colorant in the individual polymer particles.

Finely particulate polymer for stencil ink

Growing community of inventors

Tokyo, Japan

Toshiaki Kano