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the whiter-than-white, bluey whiteness promised by Daz laundry detergent

Random trivia: In order to combat the fact that clothing gradually turns yellow as fibres are damaged, modern laundry detergents contain dyes which fluoresce blue under ultraviolet light. The "bluey whiteness" really is exactly that!

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And in the old days, to hide dirt and especially to mask the yellow sweat ring that develops around the collar after many days of hard labor, companies issued blue shirts to their workers as a uniform. Hence, "blue collar" work.

You can actually buy bluing agent for your laundry, it's pretty old school, but actually adds a bit of blue dye for the same effect.

http://www.mrsstewart.com/

adds a bit of blue dye for the same effect

Blue dye != blue fluorescent dye. Blue dye simply absorbs non-blue light; blue fluorescent dye absorbs UV and emits blue light.

Ok then, a similar effect :)

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