Phthalide compound and a near infrared absorber and a recording material each comprising the same compound
US5627287A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 24, 1995 |
| Grant date | May 6, 1997 |
| Priority date | — |
| Expiry date | Jan 24, 2015 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D405/06
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A phthalide compound of general formula (I) and a near infrared absorber and a recording material each utilizing the phthalide compound are disclosed. ##STR1## wherein ring A represents a substituent group of the following formula ##STR2## where the other substituents are as defined in the disclosure. The near infrared absorber and the recorded image on the recording material absorb strongly the near infrared region with no appreciable absorption in the visible region of the spectrum. The near infrared absorber is colorless or pale in color and yet highly capable of absorbing near infrared radiation. The recorded image on the recording material can hardly be read with the eye but can be read with the OCR. Moreover, the effect on the developed shade of any concomitant color former in a recording material is minimal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.