What is_page do I use for my Posts Page

I have a static front page on my wordpress blog and a different ‘blog’ page set as the Posts Page.

I’m also using the is_page reference to create breadcrumbs on my pages. However I can’t figure out what is_page I have to use.

My blog page is named Blog and I’m using my custom blog.php template for that page. However

is_page('blog')

doesn’t seem to work.

Please help!