Color development writing compositions and writing instruments
US11192395B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 10, 2018 |
| Grant date | Dec 7, 2021 |
| Priority date | — |
| Expiry date | Jun 3, 2039 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08K2003/265
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Writing compositions capable of undergoing a color development when brought into contact with a specific substrate including a color change-inducing compound are provided. Writing instruments comprising such writing compositions are also provided. Application of the writing compositions to surfaces other than the intended substrate will avoid color development and prevent staining of the unintended surfaces. The writing compositions include at least one mineral filler, at least one leuco dye, one or more lipids including one or more waxes, one or more fatty acids, or one or more fatty acid esters or fatty amides, titanium dioxide, and optionally at least one additive.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.