How to flatten multidimensional associative array to just strings in PHP?

I currently have an array that looks like this:

Array ( [Name1] => Array ( [0] => trait1 [1] => color1 [2] => hat1 ) [Name2] => Array ( [0] => trait2 [1] => color2 [2] => hat2 ) [Name3] => Array ( [0] => trait3 [1] => color3 [2] => hat3 ) ) 

How do I convert that to a string so that I can write it to a text separated by delimiters? So that Array1 looks something like this: Name1,trait1,color1,hat1?