Sharp pixel pattern looking like some sort of fabric.
Source Dmitry
A beautiful dark padded pattern, like an old classic sofa.
Source Chris Baldie
A free black metallic background pattern. Here's a new pattern I made that looks metallic.
Source V. Hartikainen
From a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
Remixed from a drawing in 'Works. Popular edition', John Ruskin, 1886.
Source Firkin
Love me some light mesh on a Monday. Sharp.
Source Wilmotte Bastien
From a drawing in 'The Quiver of Love', Walter Crane, 1876
Source Firkin
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
White fabric looking texture with some nice random wave features.
Source Hendrik Lammers
Prismatic Groovy Concentric Background 5 No Black
Source GDJ
Prismatic Hypnotic Pattern 2 No Background
Source GDJ
This is the third pattern called Dark Denim, but hey, we all love them!
Source Brandon Jacoby
The image a seamless pattern derived from a weed which I can't identify.The original weed image is from here:https://jp.pinterest.com/pin/500744052301423641/
Source Yamachem
You just can’t get enough of the fabric patterns, so here is one more for your collection.
Source Krisp Designs
Prismatic Groovy Concentric Background 5
Source GDJ
Green Web Background, Seamless tile.
Source V. Hartikainen
Inspired by an image that was uploaded to Pixabay by geralt
Source Firkin
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
A free background tile with a pattern of pink bump dots. This background tile is sweet! Moreover, it's designed for use as website backgrounds.
Source V. Hartikainen
Prismatic Hexagonalist Pattern No Background
Source GDJ
Background Wall, Art Abstract, Blue Well & CC0 texture.
Source Ractapopulous
Sort of like the Photoshop transparent background, but better!
Source Alex Parker
One more from Badhon, sharp horizontal lines making an embossed paper feeling.
Source Badhon Ebrahim
A seamless pale yellow paper background with a pattern of animal tracks.
Source V. Hartikainen
A heavy hitter at 400x400px, but lovely still.
Source Breezi