Dr Virago Pete's De-Yellowing Service

As Neutral colored plastics age a noticeable yellowing of the color happens to some but not all objects.

This yellowing of the plastic is very noticeable in
1. Computer cases and accessories like mouse, printer, disk drives, etc
2. Office Equipment Fax machines and copiers and desk handles etc
3. Home appliances Refrigerator handles, Washing machine knobs, air conditoner parts etc
4. Other beige colored objects (toys, tools, parts etc)

Severely Yellowed plastics look Brownish Orange or Orange-ish Brown. Some vintage items have darkened or yellowed unevenly.

I have successfully de-yellowed
1. Amiga 1000 and Disk drive (My own prototype for this successful process years ago) shells
2. Commodore 64 computer/VIC-20 and drive shells
3. Laptop shells
4. Mice and printer shells
5. Hon Desk Drawer Face plate plastic inserts
6. Box Fan Feet
7. Fax machine shells
8. Apple IIe and Disk drive shells
9. Compaq 10179 portable PC keys (Compaq PCs have a beige shell which doesn't yellow- only the keys yellow)
10. Dot Matrix Printer Shells
11. Refrigerator handles and plastic faceplate parts
12. Stove knobs and decorative trim pieces
13. Toys
14. PC case decorative front faceplates, diskdrive faceplates, mice, removeable hard drive shells, etc
15. Game System Shells
15. Too many to list

How do you know what is the normal color? By taking it apart carefully- you can see the color of the same plastic from the inside. Surprisingly- the monitor you thought was yellowish beighe is really supposed to be nearly white or almond color.

So what causes this yellowing?
This is a debatable point. Some say it is additives to the plastic to add fire-retarded features (bromide). Some say it is fingerprints which cause this yellowing. Some say it is the chemicals within the plastics coming to the surface.

My view is it is the release agent sprayed into the mold. When a plastic part is molded- a metal mold is created and mounted inside a machine- in many cases of manufacturing a plastic injection molding machine is used. This machine forces melted plastic into the metal mold. Then the plastic part is removed and the cycle continues to make an second part, third part etc. The plastic likes to stick to the mold and for easy evacuation of the part - a release spray is sprayed into the mold. My personal view is the release spray causes this as the residual release spray remains on the part and causes a chemical change in the surface of the plastic.

Cleaning the plastic doesn't get rid of the yellowing because the spray release has already caused a chemical change. This chemical reaction can be sped up by air, temperature, humidity, exposure to sunlight, and fingerprints.

My process reverses the color change without removing any plastic. No abrasive is used. Only mild chemicals are used to reverse the very thin surface layer of yellowed plastic.

I don't make any guaranty on re-yellowing in the future. I only de-yellow. I have been deyellowing for several years and I see no re-yellowing. Will it gradually re-yellow over time? Say a 20+ year old computer which is yellow- will it reyellow 20 years from now? It is possible- that is unknown. Maybe it will or maybe it wont. I honestly don't know.

Need a part deyellowed?

1. Take apart your machine or device
2. Send only the pieces which are yellow (no motors, no screws,  electrical circuits etc- just send me the platic shell)
3. Remove stickers
4. Remove nameplates (glue metal nameplates back on later with contact cement)
5. You can do alot of damage by dissassembling like breaking tabs, snaps, bending nameplates, etc and make a mess much worse than a yellowed computer. A highly skilled person will be able to take apart their device and send me only the plastics for deyellowing)
6. My max part size is about 8" x 36" x 18" at the present time (sorry no yellowed monitor cases as the size is too big for my deyellowing tank)

Dr Virago Pete
Telephone (847) 454-7858
Illinois USA

email drviragopete@att.net