The trademark on characters is related to selling goods, if the character is used as a way of identifying an authentic seller. So, if Disney is using mickey mo

The trademark on characters is related to selling goods, if the character is used as a way of identifying an authentic seller. So, if Disney is using mickey mouse on t-shirts to identify it as a Disney manufactured t-shirt, you wouldn't be allowed to use mickey mouse on t-shirts in a similar fashion in a way that might cause consumer confusion about who manufactured the t-shirt. If Wolverine was in the public domain, then they couldn't use a Wolverine trademark to stop you from selling a Wolverine comic book. However, if they used a _specific_ Wolverine mark to identify it as a Disney Wolverine book, then you'd be restricted from using that. Basically, trademark exists to prevent consumer confusion about who is the creator that is selling a good.