Is this proprietary work? In this case, you must follow the guidelines that were established by the non-disclosure or intellectual property agreement between you and the company employing you. They may ask for example that you keep brand names or product information secret on your publicly accessible records and keep a separate translation notebook to relate cryptic names for samples to the actual product name.

Is this open-source research? You are correspondingly free to do whatever you want.

In either case, you should follow clearly traceable methods to document what data belongs to what sample. This is to happen at the first level in your laboratory notebook. Even when you are doing proprietary work, you should have a clear line of documentation from the product information to the name, date, time, and analysis method used. Otherwise, in a very blunt way of stating it, your results are essentially gossip and are correspondingly unworthy of any further scientific consideration.

Thank you sir Jeffrey,

we're working with samples bought from the market, we didn't talk or made any deal with any company, so I think that makes my research an open-source! right?

anyway I'm asking because someone told me that mentioning the real name might get me into legal troubles, will it?

Your work is "open source" in that sense that you mentioned, yes.

I think legal trouble will follow if you use the brand names and a) publish comparison results for monetary gain or b) publish any results that show how to reverse-engineer the manufacture of the actual product. Otherwise, if you submit a publication (journal article) only to compare the performance of two products in some way ... say you compare results of Dupont Dacron with 3-M Dacron in a tensile test ... then you should be ok. You are just doing the equivalent of what our agency called Consumer Reports does, for example.