What is "writing material"?

I agree with the other two. It's most likely something that you've written before so she can assess your skills in writing. I suggest getting a sample of your writing that you like and that you'd like to show off. Just in case though, I suggest you bring your full report as well. She might actually want to see both.

Hi regal,the same problem puzzled me and the first responder.Others can help you more as long as you tell more details.I am wondering for what kind of job you are going to do.may be a editor or a interpreter? I am agree with the third response.GOOD LUCK

Hi, I would have a copy of the report with me, whatever your report is about, in case the interviewer asked for a copy. However, I once worked as an editor for a smaller publication and when I asked for a writing sample I meant just that, a sample. I'm guessing the same is true here. She may want to see a few pages, maybe two or three, that demonstrate your writing and grammatical skills, your organizational and creative talent, etc. Depending on what the brochures in the company pertain to, I think I would probably try to write a similar coherent creative piece that is brief and ties everything up with a strong ending, a sample that would somehow connect somewhat to the eventual written information that will be required via this prospective job, if I knew ahead of time what that might be. If I didn't know anything beforehand about such brochures, reports, etc., and what they might contain, then I think I would try doing a short cohesive piece that pertains in some way to the company's overall mission. Good luck. I hope you get the job. It sounds like an interesting one.

Hey she ask you to bring some of your writing materials not all of them so I think even the 40 pages report is way too long, why don't you choose something lighter because as a matter of fact she might get even tired to read your long notes, so better give her something lighter but useful.

It would've been better if you indicated exactly what's the context. In one end you're talking about a report... of which exactly we don't know... story covering? Something else? And on the other, not knowing what job exactly you're applying too doesn't allow to tell what specific kind of writing material may be asked. I guess that, in general terms, and to be asked for writing material though... it's something where things should be written in a readable, coherent, fluent manner which would mean your interviewer was trying to see an example of your writing to see just how well you convey a point through the use of varied vocabulary and make sure you have good dominance over the grammar.