Stuart Semple has released the "flattest, mattest, black acrylic paint in the world" and banned Anish Kapoor from using it, as the latest development in an ongoing feud between the two British artists.

Described as a "black hole in a bottle", Semple's new Kickstarter-funded pigment absorbs between 98 and 99 per cent of visible light. It is available to buy from the artist's Kickstarter page to anyone except Kapoor.

A disclaimer online states that customers must confirm the "paint will not make its way into the hands of Anish Kapoor".

They are also obliged to agree to a legal declaration that states: "You are not Anish Kapoor, you are in no way affiliated to Anish Kapoor, you are not purchasing this item on behalf of Anish Kapoor or an associate of Anish Kapoor."

Feud started when Kapoor won exclusive rights to Vantablack

The artists have been feuding since 2016 when Kapoor received exclusive rights to the Vantablack pigment, said to be the blackest shade of black ever created.

In retaliation, Semple created the "pinkest pink" paint pigment and banned Kapoor from purchasing it, shortly followed by his Faze colour-changing paint. Now the British artist has done the same thing with Black 3.0.

Black 3.0 is not as true a black

Black 3.0 is technically not as black as Vantablack, which absorbs 99.6 per cent of light across the visible, UV and infrared spectrum. But Semple maintains that both materials look the same to the human eye.

"Vantablack is sucking up light across a broad spectrum that includes UV and infrared as well. We're only really interested in the visible spectrum so in that range it's basically the same," he told Dezeen.

"We did extensive testing with eyes because we feel like the ultimate test for a super black is what it looks like," he said.

Can be handled like normal acrylic paint

The paint is affordable, retailing at £11.99, and can be touched and handled like normal acrylic paint. This is unlike Vantablack, which is not available for retail purchase and can't be touched, as the nanotubes that make the material absorb light break under the weight of human touch.

"Other super blacks are complicated to use and extremely expensive. Most require heat, science labs and specialist training to apply," explained Semple.

"We wanted to make a super-affordable, easy-to-use paint that was familiar to artists so they could concentrate on expressing themselves – and it smells like fresh coffee."

In 2017, Semple also released a cherry-scented version of the Vantablack pigment exclusively licensed to Kapoor.

"We've got a better black now, so it's time to bury the hate so we can obliterate Anish Kapoor's black once and for all," he added.