It depends how your business is set up. If you purchased the business through a limited company you can consider the £85K as a loan from you (the director) to the business. So you will just have a “Loan from the director” account, which is a liability (creditor) in the books. In this case, you and your wife would get your money back through loan payments that the business will be making to you (plus interest).
If you are a partnership you can consider the £85K as owners capital/capital introduced.