Organic solvent based ink for invisible marking/identification
US5990197A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 5, 1998 |
| Grant date | Nov 23, 1999 |
| Priority date | — |
| Expiry date | Jan 5, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N21/91
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An organic solvent based polyester ink formulation having a fluorescing compound therein is suitable for ink jet printing applications. The ink is useful for producing invisible printing/markings on the surface of a variety of materials for identification, authentication, sorting, etc. Suitable printing substrates include porous and non-porous materials such as plastic, film, sheeting, fabric, paper, high gloss paper; metal, foils, plates; rubber; glass; cellophane; wood; and the like. The ink formulation contains at least one organic soluble polyester, having at least one near infrared fluorophore copolymerized therein, dissolved in an organic solvent. Suitable organic solvents include a C.sub.3 -C.sub.6 carbon ketone, a C.sub.3 -C.sub.6 carbon organic ester, a C.sub.1 -C.sub.3 carbon alcohol, or a combination thereof. In a preferred embodiment, the polyester containing the copolymerized near infrared fluorophore is dissolved in a solvent comprising a C.sub.3 -C.sub.6 carbon ketone and a C.sub.1 -C.sub.3 carbon alcohol.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.