Patents by Inventor Sunao Nakashima

Sunao Nakashima has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4028118
    Abstract: An excellent thermochromic material exhibiting a sharp and reversible metachromatism at temperatures within a range of from -40.degree. to 80.degree. C can be formed from (A) an electron-donating, chromatic organic compound; (B) a compound containing a phenolic hydroxyl group; (C) a compound selected from the group consisting of higher aliphatic monovalent alcohols; and (D) a compound selected from the group consisting of higher aliphatic monovalent acid alcohol esters. The excellent thermochromic characteristics of such a thermochromic material can be further improved when it is occluded in fine microcapsules having a size not exceeding 50 .mu.. Thermochromic polymers, thermochromic printing inks, thermochromic writing instruments, thermochromic paints and thermochromic sheets having excellent thermochromatic characteristics and wide utility can be prepared from such a thermochromic material or microencapsulated thermochromic material.
    Type: Grant
    Filed: December 23, 1975
    Date of Patent: June 7, 1977
    Assignee: Pilot Ink Co., Ltd.
    Inventors: Norikazu Nakasuji, Takashi Kataoka, Hiroshi Inagaki, Sunao Nakashima