More Backgrounds - "Blank Backgrounds"

There's a certain technique used in animation, where characters are placed in front surreal stylised backgrounds. No matter how hard I look, I can't seem to find the correct terminology for this technique so I'm just going to call them "blank backgrounds", because they comprise of nothing that specifically establishes setting and location but rather puts emphasis on the main animation and the mood of the scene, through use of colour and texture. It's used most famously in anime, but it has been used in western animation as well. Here are some examples:

These each use different styles and techniques, but mainly for comedic effect. Ren & Stimpy and Spongebob sometimes use them just to add to the surreal nature of the shows (often to a disturbing extent), whereas Pokemon, among other anime, uses these types of backgrounds for moments of extreme emotion or during action sequences, they are normally moving in anime as well, and because of how they are used they are normally more elaborate than the westerners' blank backgrounds.

These backgrounds are used a lot in title sequences as well, for illustrative means. The image of Spongebob there is from the intro of Spongebob Squarepants, which pretty much always uses them, because they help show off the series' bright and silly tone through the use of colour codes, and the use of the tropical wallpaper-esque imagery and the colour blue reminds the audience of the underwater setting and the typical themes throughout the series.