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 Curved Diamond Pattern 4 No Background
Source GDJ
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Never out of fashion and so much hotter than the 45º everyone knows, here is a sweet 60º line pattern.
Source Atle Mo
Dark squares with some virus-looking dots in the grid.
Source Hugo Loning
Recreated from a pattern found in 'Az Osztrák-Magyar Monarchia irásban és képben', 1882. To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Not a flat you live inside, like in the UK – but a flat piece of cardboard.
Source Appleshadow
Prismatic Geometric Tessellation Pattern 2 No Background
Source GDJ
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 textured blue background pattern with vertical stripes.
Source V. Hartikainen
From a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
Old China with a modern twist, take two.
Source Adam Charlts
Original seamless pattern with an Inkscape filter.
Source Firkin
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
Fix and cc0 to get the tile this is based on.
Source SliverKnight
Horizontal and vertical lines on a light gray background.
Source Adam Anlauf
Remixed from a drawing in 'Maidenhood; or, the Verge of the Stream', Laura Jewry, 1876.
Source Firkin
A seamless paper background texture colored in pale yellow. This seamless texture is ideal for those who need a yellow background image for their website. The texture resembles paper.
Source V. Hartikainen
Colour version that is close to the original drawing uploaded to Pixabay by pencilparker.
Source Firkin
The rectangular tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
An alternative colour scheme to the original seamless pattern.
Source Firkin
Seamless pattern the tile for which can be had by using shift-alt-I on the selected rectangle in Inkscape.
Source Firkin