たない instead of たくない

[Lomaster]

I watched 「阪急電車」today. One character said 行きたない instead of 行きたくない.
My question is whether it is a common colloquial speech or a kansai-ben. If it is the former, then are there any restrictions on using such contractions?

 

[Toritoribe]

It's the latter, a Kansai dialect.