I heard about these texture plates from my local mixed-media art group. I purchased them on sale in the toy department at Michaels. I only paid two dollars for the package which contains 12 plates (with six different designs).
To use them, I poured fluid acrylic paint onto a palette. I then pressed the texture plate into the paint and onto my art journal page.
I especially liked the pattern produced by the wavy plate. Next time I plan to use a brayer to apply the paint to the plate for a stronger imprint on the page.
I also like the pattern produced by the plate with the narrow vertical lines. The first photo gives you a better idea of this texture. I plan to experiment with this plate and different acrylic paints to achieve a heavier marking.
Here are the individual plates after they were washed. I used a wet paper towel and a bit of Dawn detergent to clean them. You could also keep a pail of water nearby to immediately clean them after use.
You might want to cut the plates into smaller pieces for ease of handling or for smaller art journals.