US 12,202,995 B2
Reverse photochromic inks, and associated methods and writing instruments
Kenneth Czaplewski, Westmont, IL (US)
Assigned to Sanford, L.P., Atlanta, GA (US)
Appl. No. 17/761,752
Filed by Sanford L.P., Atlanta, GA (US)
PCT Filed Sep. 23, 2020, PCT No. PCT/US2020/052196
§ 371(c)(1), (2) Date Mar. 18, 2022,
PCT Pub. No. WO2021/061757, PCT Pub. Date Apr. 1, 2021.
Claims priority of provisional application 62/904,889, filed on Sep. 24, 2019.
Claims priority of provisional application 62/904,900, filed on Sep. 24, 2019.
Prior Publication US 2022/0372321 A1, Nov. 24, 2022
This patent is subject to a terminal disclaimer.
Int. Cl. C09D 11/00 (2014.01); C09D 11/17 (2014.01); C09D 11/18 (2006.01); C09D 11/50 (2014.01)
CPC C09D 11/50 (2013.01) [C09D 11/17 (2013.01); C09D 11/18 (2013.01)] 19 Claims
OG exemplary drawing
 
1. An ink formulation comprising:
a reverse photochromic colorant; and
an activator or bleaching agent.