Textures & patterns help people who are looking to add creative designs to their projects. It will be so good to have textures in free versions as it will save so much time. Most designers like to get just credit of their work as an appreciation for their hardwork, so do credit them back if you happen to use any of these textures. Most of these are free for commercial uses like web designs, brochures, poster, flyers etc.
Rainbows are something that can be related to happiness, love, friendship, peace etc with 7 colors representing it. Thus using these rainbow textures can add freshness in your design.
Glitter
Colored Texture
Rainbow Glitter Texture
Bokeh texture
Cloud
stripe texture
Metallic rainbow texture
Texture 09
Texture 10
Color Me Rainbow
Cloud Texture
Texture 13
Multi-Colored Bokeh
Texture 15
Texture 16
Texture 17
Texture 18
Neon Rainbow Smoke
Texture 20
Glitter bokeh
Texture 22
6 different colorful textures
Messy Rainbow
Messy Rainbow 2
Floral rainbow
20 collection of Rainbows Source
Rainbow Seamless Pattern
18 Rainbow Themed Patterns
Velvet Rainbow
6 Rainbow Coloured Patterns
Chromatic Rainbow Patterns
BONUS