Day-glo posting, the trailer? (well, it's following the tail lights . . . )

Ian's asked What's the definition of 'day-glo'? When does it fade below being of any use?

I have no idea, although I'm sure someone with a lab. full of kit could tell him.

But it is a thing that we - or us oldies at least - have some experience of, from the days when washing powder manufacturers started putting fluorescing chemicals in to their products. Anyone remember "Daz washes whiter than white"?

That 'extra white' was fluorescent 'white' - you may have seen the effect under UV lighting in shops and entertainment establishments (I don't frequent 'discos').

Unfortunately, the 'glow' effect was short-lived, and the chemicals didn't always wash out at the next wash cycle, so gradually built up leaving a grey residue.



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