Video footage and pictures from the Oval Office show President Donald Trump signing off executive orders with a thick, black ...

There is no such thing as “black light wavelength”—so why do black T-shirts, black crayons, and black marking pens look black? Investigate a variety of black ink markers, and find out why they look ...

The same goes for blue ink pens. However, it’s important to keep ... You can pick up this dream instrument in blue, black or red. A brilliant hybrid writing instrument, the Uni-Ball Jetstream ...

Most of the black ink we use in pens and printer cartridges comes from burning fossil fuels. To reduce that, and cut existing pollution, Sharma and his team came up with a technology called ...