Blink tears preservative?

[Matt0029]

The blink tears that come in a bottle not the vials has a preservative in it. But it says its preservative free in the eye. Can anyone explain this?

[SueG]

Apparently some drops have a preserving agent which breaks down into naturally occurring substances when it makes contact with the eye. Maybe your eye drops contain this agent. The one in mine is OxyChlorite