The classic notebook paper with horizontal stripes.
Source Are Sundnes
Prismatic Geometric Pattern Background 2
Source GDJ
Alternative colour scheme. Not a pattern for fabrics, but one produced from a jpg of a stack of fabric items that was posted on Pixabay. The tile that this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Prismatic Abstract Geometric Background 2 No Black
Source GDJ
Seamless Prismatic Pythagorean Line Art Pattern No Background. A seamless pattern that includes the original tile (go to Objects / Pattern / Pattern To Objects in Inkscape's menu to extract it).
Source GDJ
A seamless pattern with green and yellow diagonal lines on top of a white dotted background.
Source V. Hartikainen
The image is a design of blue glass.How about using it as background image?
Source Yamachem
Dark pattern with some nice diagonal stitched lines crossing over.
Source Ashton
If you like it a bit trippy, this wave pattern might be for you.
Source Ian Soper
Black version of a pattern that came out of playing with the 'light rays' plug-in for Paint.net
Source Firkin
From a drawing in 'Cassell's Library of English Literature', Henry Morley, 1883.
Source Firkin
You know you can’t get enough of these linen-fabric-y patterns.
Source James Basoo
Remixed from a design seen in 'Burghley. The Life of William Cecil', William Charlton, 1857. The tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
A seamless pattern formed from a square tile. The tile can be retrieved by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
A pattern derived from repeating unit cells each derived from part of a fractal rendering in paint.net.
Source Firkin
This is so subtle: We’re talking 1% opacity. Get your squint on!
Source Atle Mo
A seamless pattern based on a square tile that can be retrieved in Inkscape by selecting the rectangle and using shift-alt-i.
Source Firkin
This background image has seamless texture that resembles a surface of gray stone.
Source V. Hartikainen
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Prismatic Groovy Concentric Background No Black
Source GDJ