"The tie is Hans." - meaning its name is Hans. I can't be the only one with this association..? :DD
Though I know very well that "hans" is a masc. possessive pronoun and can translate it correctly, still in my mind I pretty much always hear the name and it can be tad amusing time to time. ;)
"Slipsen är honom" is not correct? why hans? what is the translation in english?
I guess your suggestion would in English be "The tie is him".
Here you are looking for a possessive pronoun.
Slipsen = the tie
That's why you have to use a definite article in the translation. The rest results out of the consequences of that.
No, sin always points back to the subject in the same clause. Here, the subject is the tie, so that would be like saying "the tie is its" in English.
As Arnauti has already mentioned, that would be "Slipsen tillhör honom." If you don't already do so, please read through the entire comment section before posting to make sure what you're about to say hasn't already been answered.
Makes sense to me. For example: "the tie is not yours - the tie is his."
Kinda same if one was to say "that (/the) tie is mine".