How to pass information from a RitchTextBox to word document

How do I pass the information that is in a RichTextBox to a word document in C #.

Code:

 String strtxt = rtbVertigo.Text;


            TextWriter sw = new StreamWriter(@"D:\Users\edv\Desktop\WORD\Vertigo.doc");

            sw.WriteLine(strtxt);

            sw.Close();

            MessageBox.Show("Dados exportados com sucesso");