How to paint white ikea bookcase?

Looks like you'd have to sand it or use a liquid deglosser, then a primer.

Hope it goes well!

Light sanding or a liquid deglosser will remove the finish so you can have a good bond between your bookcase and the paint for a longterm. Here is a good instructional link to help you:

https://www.thespruce.com/freshen-up-melamine-and-laminate-surfaces-1822210

Are you looking for how to paint the inside sections or ideas for colors or designs? :)

Use sandpaper or a liquid deglosser to scuff up the surface. Then use a good primer and paint. Here's a link with more details:

https://www.wikihow.com/Paint-Melamine

Hello a bonding primer must be used. Heres a link from my favorite bloggers

https://www.thenavagepatch.com/painting-ikea-furniture/

As with primer, latex paint is a better choice for melamine than oil. After the bonding primer coat is applied, no additional sanding is necessary. Latex paint is applied on melamine with an angled brush and a foam roller, the same as primer.

Scuff the surface with fine grit sandpaper or a Scotch Brite pad to remove the shine. Prime with a Kilz or BIN primer then paint. Seal with at least three coats of water based poly. Minwax will work.

This is a particularly difficult type of surface to paint. You can try to use a paint formulated for plastic but I would most likely go with a contact paper or removable wallpaper.

Though a laminate finish is too slippery for paint to stick, paint bonds better if you "scuff" or roughen the surface first. Use medium sandpaper (120 to 150 grit) to sand the entire surface, including the edges and corners. Be careful not to overdo sanding, because some inexpensive laminated furniture is covered with a paper-thin layer of vinyl. Wear a respirator while sanding to avoid inhaling the dust. When finished, clean all surfaces thoroughly with a vacuum cleaner and tack cloth, wipe everything clean with a damp cloth and allow it to dry completely.Though a laminate finish is too slippery for paint to stick, paint bonds better if you "scuff" or roughen the surface first. Use medium sandpaper (120 to 150 grit) to sand the entire surface, including the edges and corners. Be careful not to overdo sanding, because some inexpensive laminated furniture is covered with a paper-thin layer of vinyl. Wear a respirator while sanding to avoid inhaling the dust. When finished, clean all surfaces thoroughly with a vacuum cleaner and tack cloth, wipe everything clean with a damp cloth and allow it to dry completely.

here is info on how to do this

https://homedecorbliss.com/how-to-paint-an-ikea-billy-bookcase/

Here's another Ikea piece that's melamine and painted. https://www.hometalk.com/diy/entryway/bench/ikea-hack-upcycled-tv-stand-to-storage-bench-6787872

I would use a primer of some kind before I painted. Some chalk paints like Fusion Mineral Paint have a product that adheres the paint to anything.

Wipe it down then sand it before painting. Are you hoping to use a different color for the insides?

You will need to rub down the melamine before painting or use a Special primer for the job!

It is best to sand it down or also use a liquid deglosseras well as primer.

The clerk in the paint dept will help you with this.

Though a laminate finish is too slippery for paint to stick, paint bonds better if you "scuff" or roughen the surface first. Use medium sandpaper (120 to 150 grit) to sand the entire surface, including the edges and corners. Be careful not to overdo sanding, because some inexpensive laminated furniture is covered with a paper-thin layer of vinyl. Wear a respirator while sanding to avoid inhaling the dust. When finished, clean all surfaces thoroughly with a vacuum cleaner and tack cloth, wipe everything clean with a damp cloth and allow it to dry completely.

https://www.youtube.com/watch?v=uP3cw7q_GCg