Online Portfolio Copyrights

Hello, I am a Graphic Designer. After working for several companies as a fulll time emploee and doing freelance work too, I’ve finally completed my online portfolio.
-The puprpose of this online portfolio is to show potential employers my experiene and creativity as a Graphic Designer and apply for possitions I am interested in.
My portfolio shows only projects I’ve created or have been involved in.

In today’s global world is essential for any Graphic Designer to show their work online.

A collegue adviced me that my current/past employer could sue me for copyright enfrigement for using their brand to promote myself.

Is my collegue right?
How am I suppose to show 500 potential employers in a cost effective way my extensive work?
A simple CV is not enough to show my work, and to print 500 copies of my portfolio it’s extremely expensive.

Is there any legend I can publish on my website to protect myself?

I am sure I am not the only one that have this problem.
Please let me know any suggestions, solutions, advice, etc. They will be very much apreciated.
Thank you,