Laminate is a glossy plastic - by scrubbing it with an abrasive cloth you have made many tiny scratches which are reflecting the light more diffusely.
It is possible to re-polish shiny plastics - if you search for "plastic polishing paste" you will find companies selling pastes which have very very fine abrasives which, given a certain amount of elbow grease, and the use of finer and finer grades, bring back a sheen to your woktop.
Dil Green
September 2010