is bleach or hydrogen peroxide safe for cleaning printhead?

[jtoolman]

Bleach will corrode internal metallic components pretty much instantly. Been there!
Joe

 

[martin0reg]

The bleach I once tried contains "natriumhypochlorid" and had some warnings on the lable, but not so very dangerous.. only effect was a smell of swimmingpool for a while.
There are other fluids in a drugstore, like drain cleaner containing"natriumhydroxid", probably stronger with stronger warnings on the label. Such a "power gel" successfully declogged a drain in my kitchen, but the drain in my toilet was kind of perforated by the cleaner.. this is of metal, in the kitchen is plastik.. I won't try this one on a printhead..

Anyway most canon printheads with missing nozzles can't be cleaned, because they are not clogged, they are burnt out. At least most of the canon heads I have tried to clean ...

PS: None of these heads I could clean with any kind of "last resorts" (bleach, strong ammonnia, ultrasonic device,..) Either it works with a standard solution (like pharmacist's) or it doesn't work at all...

 

[PeterBJ]

According to Wikipedia household bleach contains Sodium Hydroxide to keep the Sodium Hypochlorite stable and to prevent Chlorine gas formation if the bleach is accidentally mixed with acids.

Household bleach and pool chlorinator solutions are typically stabilized by a significant concentration of lye (caustic soda, NaOH) as part of the manufacturing reaction. Skin contact will produce caustic irritation or burns due to defatting and saponification of skin oils and destruction of tissue. The slippery feel of bleach on skin is due to this process.

So maybe the positive result akramjef had with the cleaning using bleach is caused by the Sodium Hydroxide (lye) content? But what concentration of
Sodium Hydroxide to use in stead of Chlorine bleach? Maybe a special strong version of pharmacist's cleaning solution with maybe 5% of concentrated Ammonia could also work?

But Ammonia in higher concentrations also becomes aggressive, especially if heated.