05212558 is referenced by 16 patents and cites 3 patents.

In a facsimile machine which receives transmit data based on an original that is transmitted from a facsimile transmit machine through a telephone line at its data scrambler and which records an image of the original that is transmitted by decoding the received transmit data on recording paper at its thermal transfer printer portion, in order to maintain the secrecy of the original until the recording paper is delivered to an intended receiver by making it impossible to read the recording paper itself on which the transmit data is recorded and outputted, an image by invisible ink is recorded on the recording paper. Also, the image by the invisible ink which is recorded on the recording paper is displayed by converting it to a visible image by means of a visual observation apparatus, so that only a predetermined person can read the recording paper.

Title
Using thermally transferred invisible ink detectable by exposure to invisible light of specific wavelength
Application Number
7/659962
Publication Number
5212558
Application Date
February 26, 1991
Publication Date
May 18, 1993
Inventor
Masakazu Sugano
Obu
JP
Kenzo Obata
Okazaki
JP
Agent
Cushman Darby & Cushman
Assignee
Nippondenso
JP
IPC
B41J 2/325
G09C 5/00
H04N 1/44
H04N 1/23
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