My 3xt-grandfather Henry Risien captained one of Sandbach, Tinne & Co's ships, the "Parker". I have a copy of the "Parker"'s certificate of registration in (Liverpool 1830), on which Philip Frederick Tinne is named under "Other Owners" (after Charles Stewart Parker and Henry Robertson Sandbach). It states tha P.F. Tinne was naturalised by Act of Parliament 17th June 1823. Also listed is John Abraham Tinne. All were of Liverpool, Lancashire.
In a later entry, dated 23rd Oct 1844, it states that P.F Tinne was now deceased and that the "Other Owners" had transferred Sixty four sixty fourths of their shares in the ship to William Robertson Sandbach.
, Philip Tinne was taken into the partnership in 1813 and it became known as Sandbach, Tinne & Co. This site states that they were importers and exporters, shipping and estate agents, mainly concerned with suar, coffee, molasses and rum, but also with "prime Gold Coast Negroes" (J. Rodway. 'History of British Guiana', 1893). This info was obtained in 2002 from a Google search - there is probably a lot more info on the web by now, maybe even the above book in digital form.
Hope this is useful